damn tarnation.. these freaking forums keep eating every other post I try to type. It's brassing me off big time to re-type things so much.
Wmaker, even with the 2-speed SC it was only about 10mph faster at its FTH. What you don't consider is that while 2-stages shifts that FTH up, it usually also introduces a rapid loss of power between the 2 peaks. The single stages are smoother with the power application and drop-off, so there's a good chance that the model 22 will be significantly faster than the A6M3 in the mid-alt range because it does not drop off.
I don't believe you are accurate in your assessments of the wing area and horsepower. You might be comparing the later A6M5b horsepower, but the M3 did not have the redesigned aerodynamics nor the redesigned thruster stacks on the exhaust to increase actual forward speed. The engine was still in an inefficient state and installation, and could not produce the speed and performance of the M5b we have in-game.
Your are saying that wing area has nothing to do with climb whatsoever, which is just wrong. We have examples of how this is wrong. We have had many previous discussions on these forums on the matter, and it all plays into the rate of climb (weight, speed, excess thrust, lift, drag, etc) and a general concensus might be that excess thrust is what really dictates climb rate. However, the A6M3 did not have that much more thrust than the Model 22 it replaced.
Then let's see about your comment that clipping the wings would change nothing. We know that's not the case because we have 2 nearly identical planes in AH right now. The spit 8 and 16 share the same airframe and the same engine. Their climb rate charts are nearly over-laid duplicates of each other. However, one has clipped wings and one has 280 lbs of extra gas onboard.
Surely you're not denying that heavier planes climb slower, right?
Identical power planes, identical airframes (sans 1-2 minor points) and yet the extra wing area on the spit 8 is more than enough to make up for 300lbs of extra weight and drag. Or, to state it the other way around, clipping the wings on the 300-lb-lighter spit16 drops it down to "merely" the climb rate of its heavier, draggier, brother. That alone tells you that clipping wings reduces climb rate to some extent. You can't totally ignore it.