MSG, Tuning: error 1.04

I tuned on transmitter-based tuning, and my log is full of lines like this now:

MSG, 319548646, Tuning: error 1.04

What does this message mean?


Found an answer here: Questions and observations from my Quadplane maiden

That error means that the ratio of the RMS P term to the RMS D term has dropped below 3.0 while tuning the P or D rate terms for roll and pitch. It is based on the idea that it is bad for the D term to play too big a role in controlling an axis.