When Harry Shearer joined the cast of Saturday Night Live in the fifth season, they didn't make an official announcement right away that he'd be a cast member (and he was announced as a "featured player" for his first month), when they began the "featured player" title and promoted many writers to featured player, with Shearer being the only main cast member. It was to the point that the cast and crew didn't even realize he was a cast member instead of a featured player.
And yet in the season six premier, when the new cast compares themselves to the cast of the first five years, Gilbert Godfried says he's a cross between John Belushi and "that new guy from last year who nobody remembered the name of". At least they acknowledged that there was a new cast member (and Elliot Gould knew he was talking about Harry; he may not have said the last name, but at least he was acknowledged for those unaware).
I've also seen things that say that the cast resented the writers in the fifth season because, with them becoming featured players, they felt they were more focused on creating good roles for themselves than for writing good sketches. But weren't most of the main cast members writers as well? Didn't they write good parts for themselves, or did the cast member/writers actually do plenty of writing for sketches they were not in (I'd like to be a cast member and writer of a sketch comedy show and write as many good sketches that I don't appear in as I do ones I do)?
Some time in the last year, I saw an article about the Muppet sketches, and it talked about the time when Chevy Chase volunteered a substitute sketch when the Muppets couldn't make it. The article said that the sketch was pretty much mocking the Muppets. I've seen that one before, and I had no idea it was meant as a mockery (I saw it as further evidence that Chase was one cast/crew member who didn't dislike having the Muppets on the show, additional evidence being that he wrote one of the last Muppet sketches which was also one with a rare hopeful ending at a time when most sketches were about them being fired, and the fact that he had a cameo in Follow That Bird).