Ah, I'm a dummy. Should've assumed you looked through there! My brain is now not-as-mushy so I'll add something below.
Agreed! I didn't do this and I think it really hampered my success. I also wrote a paper and submitted it that was (apparently embarrassingly) out of touch with a lot of recent and foundational work on the topic. So, being super up to date in your WS will really impress the adcomm.
I know this can be a controversial piece of advice but I firmly believe that contacting POI is very, very important, if done well. That is, don't just shotgun, mass-email a bunch of POIs hoping for the best, but do research about their work, the program, and try to have a good phone conversation with several that allows you to demonstrate your readiness, inquisitiveness, personality, and that you know you'll be a good fit for their program. I mentioned elsewhere already, but I'm convinced that my doing this helped me get a wait list spot rather than an outright rejection at a school or two.