I find it unlikely that lag in the traditional sense was what was causing the car to be slow off cautions and restarts. It wasn't like it was just the exit speed off corners. When Dixon's stint ended and Briscoe hopped in the car was noticeably slower for a number of laps, and it seemed to me to be more than just filling the car with fuel or swapping tires would account for. Seemed like when everything got cycled on and off, something was unhappy for a couple minutes. I assume they switch calibrations when under caution as well, so same deal. I did hear the #67 was smoking from the tailpipe during the final hours of the race under caution, but not under WOT. Could all be my imagination.
I'll also leave you with this: The car was middle of the pack in terms of fastest lap. There were a couple cars faster, a couple cars slower. That was with the GT seemingly coming off the corners at a leisurely pace after making up ground under braking and through the corners. This was in its second race where the team is, let's call it, "pursuing reliability." I think Spa will probably be the first race pre-LM where you can truly say the wick has been turned up all the way.