Pound also had some kind of input into Joyce's Ulysses, and then told Joyce to piss off after seeing Anna Livia Plurabelle. Pound was not the only one.
Pound was a sort of den mother to some of the moderns in that crowd. I've read that at one point Joyce wired Pound desperately for money; Pound was hard up at the time, so he sold his couch and sent the proceeds to Joyce. Joyce spent the whole wad on a piano. The story may be apocryphal, but it sounds about right.
danlowlite has a strong point about the need for editing in The Waste Land; Eliot's late work, which went to press just as he conceived it, was painfully flabby stuff.