That was an excellent article - too bad you don’t write that kind of stuff any more - which not by chance is complaining about perhaps the most problematic component of WITE 1. To be very honest with you, I did personally did not understand what that paragraph in the manual you quote meant until I spent quite some time experimenting. You weren’t the only person out there running the same combat 10 times, but what you did not do, which I did, was to repeat the experiment switching off ground support (I am not sure you could do that when you wrote the article, though).
It is an old article - written 7 years ago, barely five months after the release of the game. Today WITE 1 - or rather, WITE 1.5 after Dominik took to himself to keep improving the game - is a game much more capable of explaining itself. And my remark was made in the present, not the past.
For instance, sometime in 2013 it was added the ability to see the “combat details”, which broke down the effect of enemy combat power for you understand the impact of air power by means of uncovering one of the “secrets” of WITE 1. Disruption - a temporary parameter that tracks the degree of cohesion of a combat unit (the higher the disruption, the lower cohesion and generally, ability of the unit elements to participate in battle) was now in plain sight.
Before that the manual did refer to it, but in a scattered manner which did not really help players appreciate how important that factor was (and is) or that it was tracked on a per element category basis. So it could be that your artillery pieces were more disrupted that the infantry due to air attack, leading to less batteries not being ready to make a contribution to the unit firepower as big as it could. Since combat happened in a number of stages, at ever decreasing ranges, disruption conveyed a decreased ability to disrupt attacking elements as they were coming to “contact”. And this in turn had the effect of those attackers doing more damage and disrupting more of your unit elements, and so on…
Setting the air commitments was a rather obtuse way to talk to the AI, and to this day, I don’t know exactly why an overview of how aircraft allocation happened wasn’t included the manual. The manual was being developed by volunteers, and the forums were very active… for later revisions of the manual somebody did the job of combing the forum for nuggets of feedback and clarifications, but it is not a very fun stuff to invest much time on. So now, barring firing an email at Gary Grigsby or Pavel Zagzin, I think you will be out of luck getting a precise answer. But from memory, as I think I read a very long detailed explanation years ago, the most important factor was range to the target hex.
Other aspects of the game were way better documented: there were even examples illustrating the rules :) While I was translating the Ground Combat rules documentation/discussion I added quite a few more examples of rules resolution that I verified personally with the engine. I want to think that some Spanish speaker read those examples and found them useful to understand the range of possible outcomes to rather abstract rules. That took me quite some time!
2by3 I think raised the bar significantly with the documentation for WitW. Not incidentally, you were presented with full page guides that focused on transmitting the essentials to the players on gameplay. Note that in WitW we have a separate air phase too… which probably takes way too long to resolve, but that’s part of the other response :)
To finish a very long post, there’s also this thing with Gary & Joel’s games that I kind of like. You need to experiment to figure out things. Compare playing Minecraft in 2011 to doing so in 2018. Nowadays you go to a wiki and you have an exhaustive list of recipes for crafting stuff. Do you want to achieve X? Easy, go there, and do backwards chaining :) Back in the day, well, you just had to go and find out. I like games that tickle my curiosity… but making those games is a delicate balancing act with royally annoying many other players.