Positioning penalty is in my experience FTM 3.05 totally irrelevant for air attacks. This is quickly realized if you try to bomb an AI (or player) megastack fleet with 40+ ships and it will take pretty much no damage. At least the damage being spread out over all ships do much more to reduce it then any potential increase.
I haven't seen any enemy fleet end up in shooting range with my carrier groups either. And I have seen nothing to suggest ships with bad positioning take more damage from naval guns/torpedoes. If you have done a real analysis on this I would be interrested in seeing it.
Max hull size before penalty was reduced because ship hull sizes were reduced. A BB used to have 4.0 hull but now have less then 2.0 before techs.
Thanks for the explanation re: the changes in hull size & penalty. I know that positioning won't impact air attacks and never meant to imply that. It's air based combat so those rules apply. I have read that it impacts ability to retreat which is why I said "not nearly as important" for CVs rather than irrelevant. Maybe it impacts CVs ability to avoid naval combat entirely. I have no idea.
As for the AI mega stacks, one of my BB fleets was attacked by a 61 ship AI mega stack. Scrolling through the enemy fleet list during the battle, I could see that ships, mostly escorts, were taking damage, but it was completely spread out. Poor positioning can create a lot of friendly fire damage. When I first started playing and didn't understand the mechanics well, I go so frustrated that I couldn't sink this one,lone IJN CV (Kaga or Akagi I think) that had zero organization and barely any strength that I attacked with five BB fleets at once - 55 or 57 ships total. Well, my mega stack had literally almost zero positioning (0.8 if I recall correctly). Almost every ship of mine got damaged and I lost two BB + several DD. The IJN carrier didn't get hit once and retreated. After that I spent considerable time reading up on positioning/stacking etc.
In retrospect, writing "less damage overall" would have been better than specifically mentioning enemy guns/torpedoes. I don't have any hard test data rather it's based upon what I've seen during game play. While learning the game I've started over a couple of times for various reasons (noob mistakes LOL). I'm using the battle plan as last time and the AI reaction so far has been very similar if identical. A few early battles involved the same fleets as before. The fleets are identical as well except for one less escort per fleet (i.e. CL for carrier fleets & DD for battleship) which were removed due to better understanding the FTM stacking penalties. Fleet commanders are also the same as is the relevant ship tech levels. In short, in terms of naval battles, only major change this game was that I ramped two or three levels of positioning tech for BB, CV, CL & DD. Combined with a much lower hull size penalty, my current game fleet has about a 25%+ higher average position per battle. Not only am I sinking ships much faster, but I'm taking about 2/3 less damage over all - CVs included. Previously I lost 1 BB (very close to losing two more) 3 CAs, 2CLs and 8 or 9 DDs. So far (and I'm further along) I've lost one DD and only once has any of the CV fleets been damaged. Last game, all three CV fleets got banged up to some degree.
Clearly there are other factors involved, but given the fact that both games are nearly identical in approach, apart from fleet average positioning, and the consistent dramatic decrease in damage taken, my conclusion is that fleet positioning played some role in the results - even if indirectly rather than directly (i.e like hull size or sea defense). Maybe it's because a much higher rate of damage/sunk ships means less enemy attacks per battle, and I'm sure I'm taking less friendly fire damage. Perhaps the higher CV positioning give a great chance to avoid naval combat altogether.
Carriers and and transports do not have a sea attack, so what role does positioning play for those ships? The positioning section in the manual doesn't say much other than CVs & transports will try to avoid naval combat. As I mentioned above, my thought is that higher positioning for CVs = great chance to avoid naval combat. Pure conjecture on my part though I've read that positioning factors into a fleets ability to retreat which is somewhat similar concept. You mentioned that your CV fleets stay "out of enemy gun range." What is the typical positioning stat for those fleets? Do they have any tech bonuses or large stacking penalties? One would think poor positioning would result in some negative consequence to CVs & transports. Certainly CAG attacks and defense thereof are not affected. It doesn't add to sea defense so what's left other than chance to avoid/escape naval battles? I'd like to see some clarity on this issue as well.