I suppose I am an affecionado. I can distinctly tell which of the major WB animator/directors did any Bugs Bunny cartoon up to around ~1980. (I refuse to recognize the awful awful cartoons after that as actual Bugs Bunny cartoons). The difference in animation between Chuck Jones, Tex Avery, Bob Clampett, Friz Freling, etc. Note that it’s not just Bug’s head and body (though there are clear differences there), but the way the characters move, the timing of their motions, backgrounds style, balance of scene, etc. Just about everyone can tell a good Chuck Jones cartoon from the others, even if they aren’t sophisticated enough to understand what is different.
Just wanted to note that the character changes noted above – Daffy Duck’s appearance, and Bugs Bunny’s , and especially Elmer Fudd’s – were prettty much deliberate and inended. The OP asked about keeping consistency from animator to animator (within, I suspect, a single cartoon), which is a differenmt question. As I noted, even for a single cartoobn you can get variation. (That’s sometimes intentional, too. Look at Jessica Rabbit – the size of her hands varies from shot to shot. Sometimes, I think, it’s because the animators were animating directly over a real actor’s hand – as when she grabs Eddie Valiuant’s tie during her singing number – and sometimes it’s for other reasons. In some shots it seems they deliberately made her hands tiny in order to emphasize her already considerable bust.)
It’s sometimes really easy to spot the key pose frames in even the best animation (though it’s much easier to spot it in low rent stuff, like the TV Disney) by the way the in-between frames seem to move from pose to pose at a very even pace, when it should be more gradual. It comes across a bit jerky.
In Disney’s Beauty and the Beast the look of the prince changes radically (and not for the better) between the transformation and ballroom scenes at the end. Very distracting…