You are correct on all counts. Baked into the motor matrix code is motor output slewing. In short, this derates the PWM rate of change. This code does way more for the Solo's protection than the max PWM parameter. It is a total hack of a fix, but it was really the only way to address the problem without redesigning the ESCs. Believe me, the developers behind it hate it more than we do. It is crippling to the Solo's potential performance in the sky.
During changes in load, there is ground lifting condition on the ESC. This ground lifting results in the ESC seeing voltage drop from 3v to less than 2.5 volts. When the voltage drops below 2.5 volts on these ESCs, the signalling simply stops. The motor subsequently stops. And down you go. In most cases, the signalling comes back on within a second. Given enough altitude, the copter can often recover from the tumble. Mine did thankfully. But not before scaring the ever living crap out of me. When this happened to me, it was actually two ESCs that shut down at the same time, then came back on. Soo all that stuff the developers say about it being risky... they're not lying.
This very topic was discussed in the weekly developer's conference call on Monday again. The conference call was 2.5 hours covering all Ardupilot development matters. And in that 2.5hrs, we actually had about a 1/2 hour long discussion on all things Solo master, which was great! Lots of great input, ideas, and discussion on how to proceed. Anyway, the consensus right now is we need to put this into master, and use a parameter to enable/disable it. Default would be disabled since literally nothing but a Solo with a stock Pixhawk 2 needs it. If master is being installed on a Solo with a stock Pixhawk 2, that parameter will be enabled in the parameter file. If you've replaced it with a Pixhawk 2.1 / green cube, you can turn it off again. That's our current thought process anyway.
Doing this will allow stock solo users to safely operate master. It will allow Pixahwk 2.1 solo users to safely operate master with handicap. And it will have no effect on anyone else using Arducopter.
Love it. When could it be implemented ? Any dates ?