For their operations, Brigade commanders (e-mail players) could count on Brigade-sized infantry assets, reinforced with a bit of artillery; the luckier ones got armour too. Artillery units, with a few exceptions, were usually not considered as belonging to a Brigade; in true SCW form, the Division commanders shifted them here and there. Initially, the Brigades had 3 Battalions (exceptionally 4); as reinforcements were sent to the sector, some grew to have even 5 or 6 Battalions, but the initial units were worn down by losses. Brigades started usually with 1 AT or other kind of support Battery, then the lucky ones got more; the XII International Brigade, facing the front area were the Italian tankettes were deployed, during the second afternoon managed to field an ATG or AAG or IG Battery or Section per Battalion.
While offensive operations were almost always carried out with at least artillery support, and sometimes with a bit of armour support, several defensive positions were held by infantry units alone, for lack of anything else. As a rule, the defenders would be dislodged or (rarely) destroyed,... sooner or later, and at a cost. But, judging by the orders and comments, Brigade commanders often were content with such an outcome, infantry alone being used as a blocking, delaying, disturbing factor. If an infantry battalion alone had, by occupying an hex the enemy needed, forced it to deploy, attack, wear down units and lose time, the poor bloody battalion had done its job. If it managed to withdraw, although a bit battered, so much better. If not... you can't make an omelette without scrambling the eggs. A prime example is the 2nd "Valdepenas" Battalion, a Green training unit that was thrown in the teeth of the swarming Campesinos, delayed them for a little while and then was rebuilt that night after having virtually disappeared. Yet, without that 1-hour delay, it is possible that Santa Julia, containing nothing but the Divisional HQ and trains, could have been reached before dusk by the Republican vanguard.
Infantry alone was also used for spoiling attacks, for diversionary actions (famously, the independent formation known as the "Grupo Almodóvar", of the El Campesino Brigade, played havoc during the night of March 1st behind the enemy lines - and it was Company-sized), for harassing raids, for garrison duties, to hold lines where nothing else was available... Probably the most gallant behaviour by an infantry Battalion all on its own was that of the 2nd "Valladolid" Battalion. It was pushed back with heavy losses by the initial El Campesino's onslaught. Reduced more or less to Company size it fought a rearguard delaying action, then, cut off behind the enemy lines, it harassed the Reds even as its morale began to fall. It destroyed the Commissar's Company in close combat, and went on roaming on the enemy's river bank.
When having artillery support, infantry operations became of course much more effective. The main operational employment of artillery was in the pre-planned barrages, which were decided upon by Divisional and Brigade commanders. Here, I probably made a mistake. I granted a 1-hour pre-planned map fire, at full effect and on target, every 8 hours, in application of CD2 rule 8.65. The problem is that to apply this degree of effectiveness and accuracy, probably very accurate preparations (surveying gun positions, observing ranging shots days before etc.) would be needed. So this rule should have been used for the campaign opening barrage only. Of course, both sides were equally advantaged. And more than once, this kind of fire was actually a waste of ammo, especially for any employment against non-static targets; the Brigade commanders guessed wrong, and bombed for an hour a stretch of empty road. At a certain point, the Column Lopez Cardoso got virtually all the Divisional and Corps artillery of the Nationalists, and at the beginning of a turn several places around San Miguel were a blazing inferno; but several of these positions happened to be empty. On the other hand, against known enemy defensive positions, the barrages were effective, especially, of course, with heavy artillery.
At the operational level, another important decision concerning the use of artillery was were to send the spotters - which Battalion attach them to. Brigade commanders tended to use this advantage to bolster weak Battalions, or locations under attack; after a while, as reported in the tactical notes, artillery began to be used en masse, and the spotters were deployed accordingly, in such a way that 2 or 3 spotter stands could see the same area. Seeing was a problem: at the beginning, a couple of e-mail players did not consider visibility and range limitations, and the artillery Groups could not support their Brigades effectively.
During the second day of campaigning, the Republicans began to realize that the greatest single advantage the enemy had was in artillery. So they employed air raid during the day to try and neutralize or destroy the enemy Groups, and that night a secondary but important objective of their actions was to assault with infantry, under cover of darkness, enemy gun positions. The outcomes were mixed.
The main limitation of the heavier artillery Groups proved to be the ammo supply. The Republican units started the campaign with a double ammo allocation, the Nationalist ones with three times the standard allocation; also Republicans received less resupply. The 150-155mm Batteries routinely ended up their ammo much too early for the wishes of the Brigade commanders. Even the 75-76.2mm Groups, which can receive much more rounds per ton, quickly consumed ammo with their double rate of fire and the lavish use made of them.
Counter-battery and interdiction/harassment missions were never used.
Armoured operations were carried out according to three different but interesting doctrines, that were actually used by one combatant or the other in the SCW and WWII. The 70th Mixed Brigade commander, having just two T26B platoons, used them in the penny-packet format in which they were actually employed quite often in the SCW. The platoon was attached to an infantry battalion, used as an integral battalion weapon and employed as a mobile armoured MG nest/gun pit; additionally it had the "panic" effect on the enemy, of course.
The Italian tankette battalion's use mirrored that of their historical counterparts: a swarm of fire-belching tankettes that was very effective against unorganized enemies and infantry in the open, less so against fortified positions, and bound to withdraw with losses if faced by an AT battery. Also, it suffered from the same problem: difficulty in cooperating with friendly infantry. Yet they saved Campobueno during the great night assault, probably by their simple presence (and therefore by their -2 morale modifier on the enemy).
Finally, the T26B battalion deployed with the El Campesino Brigade flawlessly applied later Soviet doctrine: mass use against weak points, encirclement tactics, breakthroughs etc. I could have described this as German Blitzkrieg doctrine, but actually the T26B even had their own "Desant" infantry company riding on them! Of course this eased somewhat the infantry/armour cooperation problems.
Several examples of combined-arms tactics have already been described above (and some others can be found in the "Tactics" paragraph). A few more can be quoted.
For instance, the Nationalists carried out an effective all-arms effort to destroy the "Apoyo" battalion, which had infiltrated at night behind their lines. Note that the "Apoyo" itself was a combined-arms outfit, being an infantry battalion with an attached FT17 company. At dawn on March 3rd, the Nationalists managed to engage it with heavy artillery first, then with accurate long range fire by the German 88mm battery and an infantry ambush by the 3rd "Xauen" Moroccans. The concerted effort was so effective that the enemy unit was wiped out.
The simultaneous final effort by the Republicans to take Santa Julia was, of course, a combined-arms operations too. Unfortunately, the only artillery support the tanks and infantry had was from one 107mm battery which, firing direct, was seen by Nationalist spotters and silenced by indirect fire. While the pre-emptive spoiling attack that the 1st "Toledo" Battalion launched that morning can be credited with most of the merit for the Republicans' failure to hold Santa Julia (they briefly occupied one of the built-up areas), a Republican tabletop player said that with the support of just a couple of off-board heavy guns they could have made it.
Maybe the most surprising and unusual combined-arms feat was carried out during the March 1st conquest of Campobueno. The Republican reserve which included the Guardia de Asalto company and a company of thin-skinned BA armoured cars, had moved there, and they included a platoon of cannon-armed ACs (capable, therefore, to stall the tankette's onslaught). But these reinforcements had spread out too thin, and one of their flanks was literally charged by Legionaries and flame-throwing tankettes, while Nationalist cavalry rushed to outflank the enemy and threat their accompanying infantry. The armoured cars were destroyed or disabled at close quarters, by a combination of rifle fire against their wheels, flame attacks, and infantry close assaults. The Guardias were forced back and Campobueno fell.
The usual one-off games have as the only logistical problem the issue of how many rounds small tanks and large guns can carry. But in this campaign, e-mail players had to worry about logistics, not as much as they real counterparts, but quite.
The main problem was for all brigade units to respect the rules for being in supply. To be in supply, a unit not only had to satisfy the requirements of the CD2 campaign rules (a line of free hexes, not occupied by the enemy, to the brigade supply train, basically on the road net), but also an additional restriction: the brigade train couldn't be farther than 10 hexes (10 kms). That's a 5-hour round-trip for the milk run, that had to be carried out by horse-drawn wagons, not by trucks as at Stolberg. The usual consequences applied to units out of supply: numbered-round ammo supplies weren't rebuilt, small-arms fire was penalized, and the morale rating dropped from turn to turn. Being out of supply because of this new rule happened in a couple of instances. During the first turn, El Campesino advanced so quickly that most of his battalions easily outdistanced the trains. During the third day of fighting, Colonel Lopez Cardoso had a couple of units out of supply because his Column, a makeshift formation, had no trains of its own, and depended from the divisional trains; once these were hastily redeployed because of enemy pressure on Santa Julia, they had moved out of the 10-hex distance.
On the other hand, the Nationalist 2nd Brigade had some units deployed to the North and some to the South. Since the latter were close to Santa Julia, and the Nationalist De Rivera Division had much more supply outfits than the enemy, those units were assumed to be supplied from Santa Julia.
Being out of supply also happened because of the usual reason - the unit was behind the enemy lines. As I said before, the 2nd "Valladolid" Battalion operated there for a while, with his morale and small-arms effectiveness being eroded. The Republican "Apoyo" Battalion, during the second night of the campaign, broke through the enemy lines and seriously damaged a Nationalist Artillery Group, but it did not last long while being out of supply. Finally, a pattern of mutual counterattacks across the Rio Blanco East of Santa Julia led, for the afternoon of March, 3rd, to a curious situation in which several units were on the "wrong" side and mutually cut the supply line.
As a rule, e-mail players were willing to risk a battalion being out of supply if they had to or if it could cause serious problems behind the lines (such as the above mentioned infantry units and, on the third day, the Nationalist Cavalry Regiment); but they were rightly afraid of having the whole brigade out of supply. Lopez Cardoso was about to withdraw some of his units to bring them in supply again, and he can't be blamed for that.
No units was out of supply for long enough to cause a really serious morale collapse; but the reduced small-arms fire effectiveness was a problem. Also, for a while the Republican tank battalion was ordered not to move and to save petrol.
Resupply of artillery rounds was not automatic, especially for the Republicans, so this was another logistical problem. However, there was not much the players could do, save ordering the batteries to keep the last shot(s).
Road traffic became an issue in two cases. During the afternoon of March 1st, two Campesino battalions had not received clear precedence orders over a bridge, and they got entangled as per the rules. The other instance was somewhat more justified as it happened between the "Avila" Falange Bandera and a Blackshirt Cohort; therefore, two units not belonging to the same command.