Here is what I did tonight:

- I found an input matrix for sensing PRC2 (PR2) in full lock, by requiring that it doesn't see CHARD:
    0.5*(REFL 9I A + REFL 9I B) + 0.83*(REFL 45I A + REFL 45I B) --> PRC2_P (PR2)
  This was the crucial missing piece that was hurting us for CHARD engagement. Now PR2 is servoed faster than CHARD using this CHARD-independent error signal.
  The REFL I input matrix is therefore
        #REFL 9I A - REFL 9I B ->  INP1 (IM4)
        ezca['ASC-INMATRIX_P_1_9'] = 1
        ezca['ASC-INMATRIX_P_1_13'] = -1
        ezca['ASC-INMATRIX_Y_1_9'] = 1
        ezca['ASC-INMATRIX_Y_1_13'] = -1
        # 0.5*(REFL 9I A + REFL 9I B) + 0.83*(REFL 45I A + REFL 45I B) --> PRC2_P (PR2)
        ezca['ASC-INMATRIX_P_4_9'] = 0.5
        ezca['ASC-INMATRIX_P_4_13'] = 0.5
        ezca['ASC-INMATRIX_P_4_11'] = 0.83
        ezca['ASC-INMATRIX_P_4_15'] = 0.83
        ezca['ASC-INMATRIX_Y_4_9'] = 0.5
        ezca['ASC-INMATRIX_Y_4_13'] = 0.5
        ezca['ASC-INMATRIX_Y_4_11'] = 0.83
        ezca['ASC-INMATRIX_Y_4_15'] = 0.83
        #REFL 9I A +REFL 9I B -> CHARD
        ezca['ASC-INMATRIX_P_10_9'] = 1
        ezca['ASC-INMATRIX_P_10_13'] = 1
        ezca['ASC-INMATRIX_Y_10_9'] = 1
        ezca['ASC-INMATRIX_Y_10_13'] = 1
- Also set the PRC2 input matrix back to (1,0,0,0) in the DRMI ASC setup to make sure the DRMI angular control guardian still works.
- Noticed that the PR pointing loop output matrix denationalization for yesterday was not in the guardian. (These were found in DRMI configuration, by requiring that none of the WFS loops need to do any work for pointing changes). Added the following to the DRMI guardian ASC setup:
        # PRC1 -> PRM
        ezca['ASC-OUTMATRIX_P_1_3'] = 1
        ezca['ASC-OUTMATRIX_P_2_3'] = -0.160 # to remove coupling to PR2
        ezca['ASC-OUTMATRIX_P_9_3'] = -0.456 # to remove coupling to SRM
        ezca['ASC-OUTMATRIX_P_10_3'] = 0.060 # to remove coupling to SR2
        ezca['ASC-OUTMATRIX_P_15_3'] = 0.044 # to remove coupling to IM4
        ezca['ASC-OUTMATRIX_Y_1_3'] = 1
        ezca['ASC-OUTMATRIX_Y_2_3'] =  0.170 # to remove coupling to PR2
        ezca['ASC-OUTMATRIX_Y_9_3'] =  0.284 # to remove coupling to SRM
        ezca['ASC-OUTMATRIX_Y_10_3'] = 0.040 # to remove coupling to SR2
        ezca['ASC-OUTMATRIX_Y_15_3'] = 0.008 # to remove coupling to IM4

 - With this setting I was able to engage the following WFS:
  - MICH was never turned off
  - DHARD was already on
  - INP1
  - PRC2
  - CHARD
  - PRC1
  - SRC2
  - SRC1
- The order above is what I expect to work best for engaging. 
- However, the PRC2 loop works so well, and has high enough gain, that directly engaging all 12 loops (6 pit and 6 yaw) at the same time seems to work.
- I tested that twice - with a rather bad initial alignment.

- I left the IFO locked in the engage ASC state - I want to see how much it drifts over night.