I got a chance to test the modified blend filter that JeffK and I came up with on Friday(alog 17256). It looks like it most does what we expected. Attached plots show X, Y and Z dofs for both stages., dashed lines are the before, solid lines are after, red is St1, blue is St2. I don't show it, but there was no change in performance below 1 hz.  I think we might be able to push the elliptical filter down a little more, get some improvements closer to 5hz, but that will have to wait while I run down other projects.

I've installed this on ETMY, ITMY and ITMX, but it's only running on the Y arm chambers, for now.

A side note, the blend filter banks for the BSC's are getting a little weedy. It's probably getting to be time to do a little clean up and make things more consistent between chambers.