I actually went to them in person. They didn't even try. They basically just looked at the USCIS online processing times and said I need to wait to that date (not the 15.5 month mark, the date they give you on the site where you put in your PD date). Two different offices did this to me. Unfortunately, after talking to Emma and the politicians' offices, you are considered within normal processing time until you get to that inquiry date. The 15.5 month mark is only when 80% of the cases are completed.
And, yes, a WOM will do something. It will either force them to make a decision or they'll file a motion to dismiss. I researched this a ton and I've yet to see a motion to dismiss filed in a CR1/IR1 case in USCIS. K1 in USCIS? Yes. CR1/IR1 at the NVC/embassy level? Yes. But not CR1/IR1 at the USCIS level. This was reaffirmed when I spoke with Jim Hacking (who I find to be brutally honest).
Anyway, we're just about to hit the 15 month mark in a few days anyway. They have 60 days to respond upon being served. In all likelihood, they won't even respond (and may not even be served) by the time we hit the 15.5 month mark.