To truly understand the internal Pink Floyd fight, The Wall producer Bob Ezrin revealed ALOT about Waters true contribution to Floyd. Waters ideas had to be made into something by more talented people. Additionally the greatest bass lines in Floyd were not even Waters playing.We know for fact Gilmour played the awesome bass throughout the Animals album. This interview is rather old but Bob Ezrin is a legendary producer and he shares some candid insight about The Wall.
Bob Ezrin Interview 2002
And they had to bring in an outside singer (Roy Harper) to sing one of their better known songs, Have A Cigar, because Waters could not sing it correctly.