Go blast some nuclear level reloads in a G20 and feel the frame flex. My 1911's or my witness don't flex. My G20 grip will "bend" or "flex" during recoil on firing.
I guess you don't feel it.
I definitely could feel the flex during the recoil stroke of the gun and it always bothered me. It still does bother me and I still feel it when I am tossing a 200 grn bullet at 1290 with 800x out of the gun.
The key is the G20 is not going to get much firing. It is now just a house gun for greeting folks at the door with. I can deal with frame flex and plastic for the reliability and 15 rounds.
10MM & 357 SIG, best things to come along since the 38 Super!