Why doesn't it work?

This film boasts a killer cast of young actors like Martin Sheen, Jon Voight, Charles Grodin, Art Garfunkel and Alan Armin. You have veterans like Martin Balsam and Orson Welles. The director is Mike Nichols and the source is a best selling novel. Despite all this, this film fails to land. There are funny bits in it, like the briefing room scene and the men ogling General Dreedle's mistress, but they are very few. Was Catch 22 overshadowed by MASH, another anti war satire?