I've had a nagging in the back of my mind for a little bit now, so I looked at the input steering mirror positions from a good time during O1 as compared to now.  This doesn't account for everything yet, since I haven't looked at the pointing of the IMC, but the current OSEM readbacks of the IMs are significantly different than they were during O1.  I wonder if part of our whole problem has been that we just have different enough input pointing that we're having PRC gain issues.

Anyhow, I'll meditate more and look at IMC pointing, but then maybe I'll try moving the IMs back to these Sept 24-29 positions on Sunday.

As a proxy for PRCgain since we didn't have the handy channel that we do now, I plot the TR_X_NORM.  On the left side of the screenshot are the September values, including the TR_X_NORM at about 1320 counts.  When we are at 50W and our (new) PRC gain channel reads 25, TR_X_NORM is at about 900 counts.