A sort of tribute puzzle today. Really fun to read up on the MERCURY / SEVEN which was an unfamiliar term to me. Sounds like it was quite the big deal back in 1959, seven men chosen as the "Original Seven." I particularly enjoyed learning about the tests that they were forced to undergo, including dosages of castor oil and (ahem) enemas. I get a picture of scientists sitting around a room, rubbing their hands together with glee as they brainstormed what would be funny things to do to these poor souls.
It's unfortunate that the MERCURY SEVEN don't split well into crossword symmetry. With last names of 7, 7, 7, 7, 5, 9, and 6, it's almost perfect! Almost. Such a pity that Gordon COOPER's last name wasn't 9 or 5 letters. So David is forced to add extra entries into the mix, SPACE RACE and ROCKET. It's a huge amount of theme material (I highlighted it all below to make it easier to pick out) but overall it was disorienting to uncover themage in odd locations, especially MERCURY and SEVEN being so distantly cross-referenced. Kind of like being on a tilt table after taking heavy doses of castor oil.
Don't get any ideas, you.
Even with such high theme density, David does well to add in the very nice DOODLER and SUPER C. Even having played trombone for 20 years, I wasn't familiar with SUPER C, but what a nice term. And some Googling shows that it's a real term, one I probably should have known.
One problem I had was the SETS / THEREON crossing. SETS up felt reasonable, and the Dickinson quote felt like it could be really anything. Perhaps a sewing-related clue for SEWS would have been better, as I doubt I'll be the only solver to have trouble at that square (although I should have known that SET and SETS would not have been in the same puzzle).
Another issue that nagged at me was the fill in the NE and SW corners. With the heavy, heavy constraints demanded by the themers, it's amazing that David was able to fill those areas at all. However, THE DIE feels like a partial to me, SASK isn't great, and ACETALS is a term I only know because of three years of chemistry. I've recently gained an appreciation of ADELAIDE'S LAMENT (written by LOESSER) from Jim, but LOESSER still feels like a missed opportunity for a nicer piece of fill. Tough trade-off. Kind of neat to cram in so much theme material, but some compromises along the way.
Finally, a great clue, really fun to see in a Wed puzzle. [Caller on a cell phone?] is hilarious for CON (what other kind of phone is a CONvict in a cell block going to make?). For me, a single great clue can redeem a lot of crunchiness in a grid. Nice to see that extra effort, much appreciated.