I realize that the P-51 CoG was moved but,

[MaxGunz]

I can get behind what you say but not how you say it. I wonder just what you expect when I've read the same material and don't come away with descriptions like yours.

In Bud Anderson's account the need to change trim was no surprise to him but as stated something you just do from regular practice, like tuning a car radio in those same times. But then from training on he was taking planes across the speed range quickly regularly.

At low speed you don't get enough air over the elevator and ailerons to make high stick forces but propwash on the tail will be high in proportion to prop speed and power and worse on the ground when the tail is down. At cruise the plane should be closest to trim neutral by design. Do you find any accounts for any plane of the stick being "set in cement" at low speed? At high speed, yes.

Trim is normal for most planes for not just speed change but engine setting change. When you change the propwash spiral you need to adjust the rudder to match though it's easily enough done first and sometimes (like the 109) only with the feet.

This is where I read/listen close to accounts, what are the conditions and are there any clues about all those things that don't get written or mentioned which is why Bud's statement starting off with how trim is one of those things and why really sticks out. It doesn't mean trim every second but in maneuvering combat it happened often and for an accomplished pilot was no big deal, something done without thought.

Still the IL-2 P-51 is trim needy as are most all of the models and in IL-2 it's not simple at all to get right (in fact it's a PITA) nor do we players have the feel of G's and slip side-pull and changing stick force that let these things become automatic. It's a pain no matter what plane, some degree of that plays a part in P-51's so how do you say how much is the game itself and how much the model? Oh, by comparing to enemy planes!

How many degrees is elevator trim? And how many clicks is the total range? A couple of clicks is barely anything!

If something needs to be fixed it also has to determined how much fix and not enter magic wand land.

BTW, plural orders of magnitude more is 100x, 1000x, 10000x, not 2x or 3x more. Please, significant is 10%, 1/10th more, and 50% more or less is extremely remarkable where 25% alone is remarkable. Orders of magnitude is not a statement to be thrown around. It has numbers attached that beg qualification despite how often number-challenged people misuse the term. Cargo capacity of a ship tends to be orders of magnitude more than that of a truck. A modern jet might fly a single order of magnitude faster than a Piper Cub. Changing trim 100x more than what Bud described you mean never removing a hand from the trim wheel.

Your 'ball' ricochets around and takes precious seconds to settle the moment you deviate from straight and level flight,

I have to be a lot more ham-handed than usual to get The Ball to misbehave anything like what you describe.

Find the date that Zeno's Flight Characteristics film was made. Clues: it's a P-51B being introduced as new. There is NO mention of the fuselage tank and CoG caveats we see mentioned later as you would expect if there was a fuselage tank and "these reports were part of the training regimen" which BTW that film was.
My conclusion is that at that time there was no concern because there was no fuselage tank to be concerned about. Still, once it is EMPTY the result *might* be the same or close to the film.
We -KNOW- that with the tank more than half full that the change was big not only from the manual but pilot accounts such as Clostermann's.

I know you have a passion for the subject but it keeps going to the fundamentalist religion level. If you get a blackboard, you could approach the Beck level from where you may never come back to sane reasoning and start using first letters in arranged words to make your own truth. Did you ever know Von Helton?