[dash_riprock]

To me, Tom Seaver is the most knowledgeable. He correctly recognizes proper rotations, and he definitely knows the pitching rules.

Especially clueless:

Tim McCarver (The Babe Ruth of clueless announcers)
Joe Morgan
The entire YES team (Sterling is the captain)
Jim Palmer (it's a good thing for him there were seldom runners on base when he was pitching)

Edit: By the entire YES team, I am referring only to Sterling, Kay and Wuldman (I'd like to know who came up with the brilliant idea to have a chick with a Boston accent announcing Yankee games). I apologize in advance to Rita for the preceding sexist comment.