The shaded squares (visible in the original puzzle) spell out the name of Chris Philpot [see a series of tweets on his twitter feed, circa January 3, 2014, culminating in Chris' own solution]. Updated January 11, 2014: Read a more detailed blog post by Chris, entitled "Never a cross word," which covers his own experiences solving this puzzle.]
Explanation of clues and answers:
1-Across: Slope moves easily = LOPES, which is an anagram of "slope" and is defined by the second half of the clue.
4-Across: Armed as Aida's lover = RADAMES, which is an anagram of "Armed as" and is defined by the second half of the clue. Aida is one of my all-time favorite Verdi operas, starting from when my mother took me (at age 6) to see the cinematic version starring Sophia Loren channeling the voice of Renata Tebaldi. Later that year, my mother made a costume for me as Radames (commander of the Egyptian army), while my poor brother Francis was dressed up as Aida (the slave girl who is daughter of the Ethiopian warrior king Amonasro), complete with a couple of tennis balls at critical spots of his costume. According to family lore, I quipped that "I would rather marry Amneris, than to die!" [referring to the Pharaoh's daughter who is the third leg of this love triangle for the ages—link just given to justly famous "tomb scene" finale]. BTW, click here for a relevant (American-style) crossword puzzle that I constructed with some of my friends to mark an important bicentennial in October 2013.
8-Across: Present time = CHRISTMAS. Self-explanatory pun, and particularly appropriate for the holiday just a week prior to New Year's Day.
9-Across: Leaves home = TREE. Self-explanatory pun.
10-Across: Trying wisely = JUDICIOUS. A wise judge tries cases.
12-Across: Park place = LOT, which is wordplay on "parking lot" and on a storied Monopoly property.
13-Across: Ring man = WAGNER, referring to the composer of The Ring Cycle (not one of my favorite operas). Interestingly, Wagner's bicentennial was also observed in 2013.
14-Across: Game in nets = TENNIS, a favorite family game [especially for me in my youth, and for my academic All-American daughter throughout high school and college], which is an anagram of "in nets" [and even gets across the fact that "nets" separate the two sides of tennis courts].
17-Across: No mas = PAS. Self-explanatory, but also winking at this.
18-Across: Ken copies old recording = KINESCOPE, defined and discussed here and an anagram of "Ken copies." Given what I was able to learn on New Year's Day about Chris Philpot and his interests, this was a particularly pleasing entry to the puzzle.
19-Across: Knight in tennis shoes = PHIL refers to this Nike co-founder, now philanthropist, and whoops (TETCBN in NPL parlance), without the pressure of creating a puzzle from scratch on a tight timeline, we would change the adjective "tennis" to "athletic."
20-Across: Up to prior hodgepodge = POTPOURRI. The first three words are an anagram for the succinct definition provided in the fourth and final word of the clue.
22-Across: N.Y.C. late, inactive period = LATENCY, which is anagrammed by "N.Y.C. late" and defined by the two words following the comma. I won't give you chapter and verse, but my parents worked in the field of muscle biochemistry/physiology, so the phrase "latent period of muscle contraction" [the several msec during which Ca++ is released but there is no change in length] was in my vocabulary from many a dinner conversation [and yes, I grew up in N.Y.C.].
23-Across: Neck lines = FRETS, a pun referring to these guitar components.
1-Down: Jack owl's tetanus = LOCKJAW, which is an anagram of "jack owl" (as per link, not as outrageous as it sounds), followed by a dictionary definition.
2-Down: Diaphragm fits sea change = PARADIGM_SHIFT, a pretty fancy anagram of "diaphragm fits." following by a synonymous buzzword for the answer, itself a high-concept buzzword.
3-Down: Help shortly = SOS; we hope you will not require help to understand how this particular clue leads to its answer.
4-Down: Tamper with a gun = RAMROD is wordplay on two meanings of the word "tamper;" compare to the dictionary definition of "ramrod" (the noun, not the transitive verb).
5-Down: Stress aid? Not! = DISASTERS, a straightforward anagram followed by a catch-phrase that peaked in popularity during the 1990s.
6-Down: The blond bombshell has more yin? Normal. = MARILYN_MONROE. The anagram of "more yin normal" gives us an excuse to contemplate an American icon (4-minute video montage with what sounds like a Gershwin soundtrack). Click here or here for more.
7-Down: Waste perspiration = SWEAT, a one-word anagram followed by a one-word definition (elegant suggestion from Roy Leban while editing this puzzle).
11-Down: Investigate Coke punch = CHECK_UP_ON, a one-word definition followed by two words to anagram yields a three-word answer.
15-Down: E. Pisces biological division = SPECIES. You won't find "E. Pisces" in any biology book!
16-Down: Hard to see or hard to saw = KNOTTY, alternate definitions of our answer word clued in a nearly identical manner.
17-Down: Visionary student = PUPIL, wordplay on two definitions of our answer word.
21-Down: Foo Fighters' response to a punch-in-the-gut = OOF, proof that even our generation has some familiarity with late 20th-early 21st century rock bands.
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