I expect you are correct regarding tightness causing problems.
I don't have personal ownership experience with 1911 pistols so must go by what I see happening to others at the range.
Invariably when a pistol fails at our IPSC shoots it is a 1911 type. I have friends that own several 1911's and they have all had problems while the Glocks, XD's and M&P's just keep on ticking.
I can not convince myself to spring for the high cost of a 1911 when extremely reliable pistols can be purchased for $500 or less.
Fit of barrel to slide is what yields accuracy other elements can be loose and still yield an accurate pistol.
I have seen Glock, XD and M&P's in 45ACP produce sub 1 inch groups consistantly at 15 yards which would be tighter at 25 feet. My current primary pistol is an M&P40 which has consistantly yielded 5/8 inch to 1 inch 5 shot groups at our typical accuracy check distance of 15 yards.
I will admit they do not produce these groups with just any ammo but the Pistols are capable. In terms of reliability my M&P has well in excess of 10,000 rounds through it and the only problems to date were related to aftermarket magazine extensions I purchased for the IPSC game. I no longer use them.
That is my view.