Centaur who was killed by Hercules / THU 9-14-17 / Burrowing South Amercain rodent / Jesse who pitched in record 1252 major league games

Constructor: John Guzzetta

Relative difficulty: Easy-Medium

THEME: DIASTEMA (52A: Formal term for the gap suggested by 17/18-, 35/37- and 54/57-Across)— it means a gap between the teeth; each theme answer has a "gap" in the middle of the word TOOTH (which is embedded in each answer):

Theme answers:

• TOOT / HIS OWN HORN (17A: With 18-Across, what a boastful guy might do)
• DO UNTO / OTHERS (35A: With 37-Across, start of an ethical rule)
• SPREAD TOO / THIN (54A: With 57-Across, overextended) 

Word of the Day: DIASTEMA—

noun

1. a gap between the teeth, in particular.

   • Zoology

     a space separating teeth of different functions, especially that between the biting teeth (incisors and canines) and grinding teeth (premolars and molars) in rodents and ungulates.

     noun: diastema; plural noun: diastemata
   • a gap between a person's two upper front teeth. (google)

This is a good idea poorly executed. Two very major problems. First, the revealer ... how do I say this? ... To have your revealer be a hyper-obscure term (I'm sorry, "Formal term") is maybe not the greatest idea if you have any intention of having the solver's experience result in a final "AHA! Ooh! Satisfying!" Or if you want your solver to understand your puzzle *at all* without the aid of a dictionary. So this ended with all the pleasure of ... googling the answer. Only then did see what was going on in the themers—which brings me to the second major problem. Maybe you can see this for yourself. Just look at the way the theme is played out, visually. Now consider what DIASTEMA means. See a problem? If the ****ing ridiculous obscurantist nightmare term your using as a revealer means "space between teeth" then that damned space better come between some damned teeth. But no. We just get busted, cracked teeth. I looked up a word for this? No. No thanks.

Only trouble in this grid is gonna come from the revealer and (surprise!) proper nouns. I happen to know DUMONT but many under 70 won't, and let's hope they're football fans because that "M" crosses MADDEN (27A: ___ NFL (video game franchise)). OROSCO will be very familiar to older (i.e. roughly my age and older) baseball fans, particularly '86 Mets fans. But a whole cross-section of solverdom will need ever cross there. NESSUS is bonkers, in that I teach stuff that he's mentioned in and even I forgot his damned name (44D: Centaur who was killed by Hercules). Personally, I died at the SHYEST/RYDELL crossing. I had an "I" there. Put it there because I thought that was how you spelled SHIEST. And then left it in for RIDELL. It's not that I didn't know the name of the "Grease" high school. I've seen the movie a billion times. But once that "I" went in, RYDELL wasn't gonna knock it out. It's a pretty bad cross, since SHIEST is acceptable and RYDELL is a proper noun. But whatever. It's fine. My bad.

Now if you'll pardon me, I have to go tie up a single LOOSE END (2D: Something to tie up).

Signed, Rex Parker, King of CrossWorld

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