So does any one have an actual list of tug upset accidents with
towplane type, glider type and circumstances?
Just off hand I can't remember any in Australia and yes even when you
use low tow the upset possibility exists after liftoff and before
transition to low tow.
We've had plenty of towplane/glider midairs which makes existence as
a tow pilot 10 times as likely to kill you as cropdusting per hour.

Mike Borgelt