Once the Boston Legal originals are finished (which is soon), if I were ABC, I would switch Saturdays with Tuesdays and run theatricals against American Idol / House.
ABC has skedded some highly promotable theatricals on Saturdays for the February Sweep, including the broadcast premiere of "Miracle" plus encores of "War of the Worlds", "Charlie and the Chocolate Factory" and the gazillionth encore of "Forrest Gump". I think these four theatricals could surely gather up bigger audiences on Tuesdays than the lineup of Just for Laughs original & encore / According to Jim / Carpoolers / Boston Legal encores.
And I would expect that the Tuesday comedy line-up would do roughly the same numbers on Saturday night as on Tuesdays.
This is a good point dumont, but I wouldn't slate the Tuesday stuff for Saturday. I would burn off Jim on Fridays along with maybe Carpoolers and save new eps of Just for Laughs for summer. Then on Saturdays go with the Wonderful World of Disney along with extra AFV repeats. On Tuesdays when needed, air an ep of Women's Murder Club.
I also like the idea of airing those movies on Tuesdays for February sweeps, and also agree with mushu not to burn off AtJ on Saturdays. After the February sweeps, I recommend adding America's Funniest Videos (mix of reruns and originals) to lead-off the night @ 8pm.