Well, I really enjoyed this puzzle thoroughly. It's a quadruple triple stack of 10-letter answers, which means 12 long answers, all of which I liked with exception of one. That's pretty impressive. Then, in addition, there's a fine diagonal of 5-letter answers down the middle. Good flow, overall.
I broke in with 15A: Browse without comment (LURK), a term I remember well from the days of online bulletin boards and forums. Does anybody still use those in the age of social networking? Once I added BOKCHOY (very nice) and ELK, I suddenly saw 3D: Fall out of line (BREAKRANKS). 1D: Crosses, as a range (CLIMBSOVER) seems just a little off, but is certainly accurate. AUDIOPHILE completes this trio. I made my mistake here, where I put OHARe at 30A: John who wrote "BUtterfield 8" (OHARA). Should have realized SHIe made no sense.
1A: Napa options, informally (CABS) is referring to the wines, which moves it up a full grade to a B-.
Despite getting TODAY, I had no more purchase in the transition to the NE, so I moved to the SW. RESPECTS moved me in. 40D: Small bomb used for breaking down gates (PETARD) is wonderful. Now I now what they mean by "hoisted by one's own petard" means. 37D: What's the point? (DECIMAL) is also very nice.
48A: It might involve someone "so fat" or "so old" (YOMAMAJOKE) is a winner, as is 53A: What to grab for the road? (HANDLEBARS). I don't love 51A: Regular joes (AVERAGEMEN), just because it feels like two words stuck together rather than a widespread term. 46D: Home of "Christina's World," familiarly (MOMA) was opaque to me, and the first M was my last square entered.
43A: Halluces (BIGTOES) should have been immediately apparent to me, as we often test the extensor hallucis longus in Neurology. But I read it as a strange version of "hallucinates". In any case, 27D: One stuck abroad? (VOODOODOLL) wins for best clue-answer pair today. Any reference to Star Trek's a winner (ENGINEROOM), and 29D: Starting line (READYSETGO) is also great.
The NE has the best set of three answers, though. I love STIFFDRINK, NOSIREEBOB, and ADAGENCIES took me a while to parse correctly (18A: They get spots out).
Very well done.
P.S. The new They Might Be Giants album is out on Spotify. I'm listening to it right now.