Air Power is distinct from Land Power in that it has increasing returns the more you build, while Land Power has decreasing returns. Having 100 divisions instead of 50 is, at most, 2x as powerful, and taking into consideration limited frontage or supply or officers or stacking penalties it can easily be more like 1.5x.
Not really, no. Having more divisions opens other doors. The entire world of tactics and strategy is not bound by frontage and stacking, any more than the world of air warfare is totally bound by air stacking penalties. The EXACT same reasons you give for air power being more effective apply equally to land power, though you seem to be unaware of it. You speak of high numbers of air wings enabling more sorties per week due to effective dilution of the target concentration, which is actually high saturation of air power, i.e. the opposite. But the effect is largely the same so we can say it either way with safety.
Imagine now 100 divisions along a battle line which only has frontage for 50 to engage at once. You call that a limit. I say it is no more a limit than having 50 wings in an AO that can only accomodate 25 on mission at once without incurring severe stacking penalties. You look at this as a World War I issue when you speak of land power, but as a World War II issue when speaking of air power, as if those divisions had no utility other than to all simultaneously assault the enemy line frontally. Here are other ways 100 division can leverage their numbers beyond what the frontage limit seems to allow:
1. They can penetrate the line at one point, form a salient, then expand that salient beyond the enemy's ability to man the now lengthened front. This will have the side effect of increasing that frontage limit way above the 50 it started at in our hypothetical case.
2. They can penetrate the line at one or two points, then form an encirclement corridor, trapping the enemy divisions within so they can be destroyed in place.
3. They can cycle on and off the battle line in an ongoing attrition battle, so that your line is always manned by high org, high strength units while your enemy's org and strength are relentlessly being reduced lower and lower until his units begin to shatter all up and down the line. Anyone who has tried taking France and going toe to toe with the Wehrmacht with a moderately historical build plan likely knows what this feels like from the other side.
And so on. So yes, it is 100% true that many kinds of unbalancing focus on one or another element can seriously unhinge the AI's ability to cope and equate to an "I Win" button in SP play. Other examples:
1. Focus your production/research on nothing but moderately cheap mobile forces, like MOT, CAV, etc, building lots of them, then just roll over your enemy in a rapid, front-wide overrun. Since AI nations will always follow the historical reliance on foot infantry, they will always be vulnerable to overrun by large numbers of even slightly faster attackers.
2. Focus your production/research on MIL plus support brigades.
3. Focus your production/research on fielding HARM along your entire front, and leverage their high armor, low softness, and high piercing to simply steamroll your enemy in a relentless, albeit slow, general assault.
And so on. Obviously some approaches are foreclosed to certain nations, while others are particularly well suited to certain nations. But there is no shortage of ways to use imbalanced build schemes to clobber the AI. Air power is only one of them...or actually two, since unbalanced strat bombing is a separate deal and also qualifies in its own right.
