The below assumes the data is accurate:
The 106 degree turn from 260 to 154 was accomplished over 64 seconds. If done the short way around to the left, this equates to 1.6 degrees per second. A fairly lazy turn here.
Then it was increased to 5.7 deg/sec. 5.7 degrees/sec is not an overly aggressive turn, but over the short period of time it was instituted indicates to me a more impending requirement to get pointed in a particular direction arose. And they are descending to an altitude associated with practice/real engine out patterns near a field used for practicing these.
It's the 5 knot per second speed decay that is more concerning. If you're at 3700' and 192 in a descent (per the data) and you intend to be at 3000-2500' (high key) and 120 or so for the profile, a rapid decel would be appropriate, but attention to stopping the decel at 120, possibly with pitch only, would be competing with, but as paramount in importance as getting pointed in the right direction for the profile. The old slow down and go down.
I believe UJC is using LOC to refer to Loss of Control, not Loss of Consciousness. The technical acronym used in the T-6 for loss of control appears to be OCF, out of control flight. Does the T-6 have a speedbrake function? edit: Further reading indicates it does.