Brilliant paragraph by Andy Greenwald (read the whole piece, please...):
It's a funny thing about television — funnier even than the time Liz Lemon turned into a Batman villain: By giving us such free and unfettered access to great talent it simultaneously flattens and normalizes the experience. The masters of the medium tend to be the ones we notice less and take for granted more, especially those rare and hardy souls we allow to age in front of us — the Lettermans, the Stewarts, the Opraii. Fey and Poehler haven't sat behind a desk since the SNL days and they remain wonderfully distinct, idiosyncratic performers — Fey a dry, mouthy vermouth to Poehler's fizzy, physicalized pop. But both women made their bones as improvisors, a comedic tradition that tends to privilege the good of the group over the ambitions of the individual. (A proper Harold is only as good as its weakest member. Anyone who's sat through a draggy "dinner party" sketch can tell you, a stray Ringo doesn't make you the Beatles, it makes you the All-Starr Band.) Accordingly, the two have spent so much time making other people look good — everyone from Jimmy Fallon to Rob Lowe has seen his talents and timing improve by proximity — that it's easy to overlook how much better they've made everything around them.