The blurb tells us that this was a contest puzzle in Lollapuzzoola in a previous year, and had a 15 minute time limit. I suspect opinions will vary on the theme here, in that each theme answer is a one word said twice, but here split into two grid entries, each clued in a different way. Thus ZOOM / ZOOM is clued with the Mazda ad slogan as well as with "quickly". The former works better for me than the latter.
Other theme answers are likewise hit and miss. I accept the Al Pacino movie reference (although I'd never heard of nor seen the film in question), but the P.G. Wodehouse book AUTHOR / AUTHOR is merely a collection of his letters. How many people would be expected to know this? Perhaps I should take this as a goad to my trivia knowledge. I did not know the Aaron Copland ballet, but HEARYE / HEARYE as a "town crier's cry" is straightforward. Similarly, the Louis Prima tune is outside my wheelhouse, but SING / SING as a prison name is common knowledge.
In any case, the duplication of the answers made the puzzle much easier than expected. I do like the addition of CHINATOWN and YOUBETCHA (very nice). The rarely-used (in music, anyway) BSHARP is fine. I smiled at the classic 34D: What generals keep up their sleevies? (ARMIES).
On the other hand, ITNO and ERNO. I can't decide which is worse. Probably the latter.
1A: Computers that are un-PC (MACS) gets a C+. It's an old joke (perhaps it wasn't so tired when the puzzle first ran). It's also the answer I put in first with 100% confidence.