The alcohol makes the rest of the sauce taste more intense. You cook it off anyway. It’s some sort of chemistry thing.
Cook’s Illustrated also has my now go-to pie crust - you add vodka to it, because it makes it wetter and thus much easier to handle, but it doesn’t chemically act like water and toughen the crust.
Many of the flavors in tomatoes are alcohol soluble. You aren’t looking for the taste of the alcoholic beverage, you’re looking for a relatively neutral alcohol that will release these flavors. Gin, bourbon, or most any other hard liquor would be a bad choice, in my opinion. Those flavors are strong and distinct. Watered down grain alcohol would work perfectly. Aside from that, I’d use white wine or the aforementioned vermouth.
Juniper Berries are used in the distillation of Gin. If you get any that doesn’t have that smell, you’ve got some bad Gin.
Or just mislabeled vodka.
You could always knock on a neighbors door, empty measuring cup in hand.
My neighbors would probably have had Everclear, which would have possibly served admirably. Whether they would have given it up, on the other hand, is doubtful - I suppose I could have traded the bourbon for it.
It probably would have. According to Alton Brown, the whole rationale for vodka sauce is that there are flavor agents in tomatoes which are alcohol soluble, but not water soluble. You use vodka because it’s pretty much just ethanol + water, and doesn’t introduce any other flavors to the sauce, as your bourbon did. Everclear would have worked, as long as you watered it down to vodka strength.
Wow, that whole post sounds very familiar…
Sorry, missed your post above. Of course, I cited Alton Brown. 
Ignorance fought. I’d wondered what the point of using a relatively tastless ingredient that evaporates anyway in a sauce was.