You’re basically 5’9. Do you think you could possibly estimate someone is 6’1 when they’re really the same height as you are? Likewise, there’s no way if you saw me or Dave that you could possibly mistake us for being your height. We’d be notably taller than you. And if Tina was willing to estimate Cooper as much as 4 inches taller than her, then in her mind he was notably taller.
Concerning Cooper seated, if anything, this would lead people would led people to underestimate his height. When people saw Cooper seated he was “slouching” (Gregory) or “bending over” (Tina). You just can’t get a very accurate measure of someone seated.
Look at the people who we know saw Cooper standing. The only one who didn’t go at least as high as 6’ is Lysne, and we know he’s not a good witness, by his own admission. Not interested in debating an inch or two, but literally all 3 stews went up to six feet tall. Reckon anyone has ever thought you were six feet tall or even six one? Hard to imagine.
If a compelling suspect was 5’9, I’d be a bit leery, but I wouldn’t dismiss them outright. 5’8? I just can’t go there. It’s why I could never go all in on Braden. Highly unlikely people could have thought he was 6’. I already have a hard time imaging someone 5’9 being estimated at 6’ by multiple people. 5’8? No way.
And for future reference, heights and weights on those WWII draft cards would not have been self reported, at least not for the most part. Your height and weight mattered to the military. They measured you in your barefeet. This is why you see so many draft records that have heights like “6’1 1/4” or “5’10 3/4”.
Oh, and Flo actually had already seen Cooper standing when she was sent to the cockpit. She checked him in at the aft stairs as he boarded.