WPNAV_LOIT_JERK function?

Today I flew four identical missions, with a couple of “loiter turns” in the list of tasks. When it came time to do the loiter turns, there was a modest lurch at the beginning of the loiter turn when flying with Arducopter 3.1.5, and a MASSIVE lurch when flying with 3.2.1. I tried varying the parameter WPNAV_LOIT_JERK from 500 to 1600 in 3.2.1 (this parameter does not exist in 3.1.5) and it made little or no difference. I wonder if WPNAV_LOIT_JERK somehow makes this lurch worse in 3.2.1; maybe there is a sign inverted in an equation somewhere…

maybe same problem as I have? gets “ok” when flying in straight line without changing heading but performs like this when changing heading at the same time?

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