It could do. The mech would obviously move with the cogs, as your arse waggles around, but wear could still be the problem.
Are the jockey wheels original and fitted correctly? The top one should have m,ore play. I seem to remember that many after market ones didn't have any play, so adjust,ment needed to be spot on across the range .
Are the cables long enough and moving freely?
Are the replacement block and/or chain worn too?
That's all I can remember about gears. More trouble than they're worth...
Do you have a stiff link in the chain?
Give a man a gun, and he can rob a bank.
Give a man a bank, and he can rob everybody.