I had a strange experience starting this puzzle. Has this ever happened to you? I started out unclear on what 1A was going to be, and then mistook the clue for 5A: "Downton Abbey" maid to be the clue for 1D. Confidently, I put in Anna. Wrong on more than one count. The wrong name in the wrong slot.
Well, it didn't take long to figure it out. I suspect this kind of mistake doesn't happen too much when you're solving with pencil in the actual paper.
My first actual confident (and correct) answer came at 3D: Band that used a pay-what-you-want model to sell their 2007 album (RADIOHEAD). The album is the stunning In Rainbows, and would have been well worth the usual cost, but we got it for free.
The theme? It's cute: taking a phrase which typically starts with a two initial abbreviation and treating that abbreviation like it's a two letter word. Reclue in wacky fashion and yuks abound. My favorite by far is 17A: Singers who go from "sol" straight to "ti"? (LADODGERS). Hah! I was also amused by PAANNOUNCEMENTS, but less so by the other three, which fell a little flat in my book.
The grid doesn't have the greatest flow, which led to the NE and SW corners turning into 5 x 5 minipuzzles. Since both are anchored by theme answers, they were a little tough to break into. I finished the puzzle in the NE, where I had IDCARDS and ADAGES but nothing else. I got the -ER of AIRIER first, and then guessed SEERS. I tried passE for 19A: So yesterday, say (STALE, could have been "trite" as well, I suppose), and then figured it out with MISTS.
Love MOTLEY. No Crüe needed, thank you very much. 50A: Pitcher of milk? (ELSIE) got a laugh. And 53A: Jesus, for one (ALOU) was a nice way to clue an ancient bit of crosswordese.
1A: Bend out of shape (WARP) was fine. C+