OK, here's the wrap on the phase testing. The "maximum null" (strange term) was very obviously at -150 degrees with both speakers, performed individually. This equates to being nearly completely out of phase in the uncorrected settings. I swapped back to correct polarity on the speaker leads and was swamped with bass.
Using Ethan's test tones through the SB and the laptop interface over the bass EQ I measured the collaborative bipole energy. Overall, the 70 - 85 hz range was up to 20 db above the rest of the bass range. I ended up cutting this area 8 - 20 db. This makes intuitive sense but was still quite a surprise since the old settings were carefully calibrated.
Ethan's tones are in 1 hz increments. After going through the difficult sections several times I got plus/minus 2 db in-room from 25 to 100 hz. This was the lo-tek strategy. Overall at this point I don't trust the optimization of this EQ set - I have about 6 programs that evolve over time. After these experiments I will need to start completely from scratch at some point.
For now, everything sounds really locked in, like I want to listen more than scratch my head and play with measurement protocols. I know, completely shocking.
Happy Sunday, especially to everyone that gets an extra hour of it.