Were you as excited as we were when we saw the two-letter spaces? I called out to Frannie immediately because it was obvious something was up. Something beyond a standard rebus, that is. The trick, or at least the concept of the trick, was brought to light quickly, though, when SANANDREASFAULT (7D: Site of slippage … both geographically and in this puzzle) (I thought immediately of "subduction zone," but no.) went in with just two crosses - the N of TONI (18A: "Beloved" author Morrison) and the L of ELMS (62A: Shade providers). Both were written straight across at the time, but luckily the important letters were in the right place.
Which brings me to my second point - didn't this, aside from the fault line, seem a little easy? I often think that when there is a trick in a puzzle (backward entries, rebuses, numbers, etc.) that they feel they have to be a little extra easy in other places. On my first pass through I filled in quite a bit immediately, and when I got it back from Frannie there was precious little left to do. Now, you might be asking, "But Horace, thirty-five minutes ain't exactly smokin', what happened?" Well, I'll tell you what. I spent a third of that time looking for an error! I tried shifting the fault around, I fretted about the single-letter answer T (65A: ____-square), and tried to see where I might put two Es… ( I guess they are a casualty of the earthquake!), I went through all the Acrosses and Downs, and on the second time through I came to SiD again. I had put in QUAi (40A: Unloading point) on that first pass through, and when I got to 36D: Barrett of Pink Floyd, I had thought to myself "Gee, I thought his name was spelled with a Y…," but at the time I was already lost in the idea of the "fault," and how it would play out, so I didn't think twice about it. Well, yes, this very long, boring, story is just to say that there is a Y in it, of course, and the fact that I knew that should have saved us nearly a third of our time. But sometimes it goes that way.
All that trouble notwithstanding, we enjoyed this one. It's a little disconcerting to look at the grid and see things like "TONH," "BRELO," and "SUTE," but then, the San Andreas Fault is a little disconcerting, too. Other bloggers sometimes complain about "nonsense in the grid," but I feel that one must accept a little unpleasantness now and then, in crosswords as in life. Once you understand it, you can get through it to see the beauty.
Lastly, just a few shout-outs: ENZYME (41A: Food processor?) (nice!), CUBED (44A: Like some numbers and beef) (odd & good), ZAPPA (1D: Rock and Roll Hall of Fame inductee with only one top 40 hit) (interesting), PARSE (48D: Carefully examine) (Two days in a row!). The two "slip" clues were a nice touch. And, finally, I was glad to read that the answer to "16A: Who has scored more than 850 points in an official Scrabble game" was NOONE, 'cause that's a really high score.