Here are some constructors’ comments about The Nation’s Puzzle #3232. 
1A BILLINGSGATE Abusive language in Montana scandal? (12)
Use of the -gate suffix for even the most inconsequential scandal is a blight on the general rhetorical landscape, but it can be a source of fun for wordplay aficionados. Many years ago we built a puzzle (not a crossword) around a list of various -gate words, including MITIGATE, INVESTIGATE and DIVAGATE, which involved a sexy soprano.
12A ELYSIAN When you speak, dropping a vowel sound is heavenly (7)
A not very common homophone of a not-very-common entry, but we like it.
13A IMPAIR Damage demonic appearance? (6)
Some solvers questioned this clue, saying that “demonic” would correspond to the adjective IMPISH, not the noun IMP. We would agree if this word stood alone, but we read the clue as a “whole thing” charade: “demonic appearance” defines the noun phrase IMP AIR. We put the question mark at the end in the hope it would mitigate this concern.
27A FAULTFINDERS Hypercritical types—seismologists, perhaps? (12)
You, dear reader, are not a seismologist, are you? If you are, please enumerate our faults in the comments!
3D INCOGNITO In part of machine, a bug: wheel is not readily identifiable (9)
A four-part charade. When using “wheel” for O, we are referring to the shape of the letter. Similarly, “horseshoe” would constitute legitimate wordplay for U.
5D GAS PEDAL “It makes the car go,” Unser said with difficulty (3,5)
Al Unser is the senior member of a race car dynasty. (Does he know his vehicle of choice is a palindrome?) This clue, once again, is a “whole thing” charade, and thus in our mind there is no problem with the order of its parts.
7D TRAIL MIX What slow cowboys do in early Westerns: snack (5,3)
The actor referenced in this clue was Tom Mix, star of nearly 350 oaters during the silent era.