"And I used to do something very similar. I'd run an OPT calculation with no derate and take note of the V2. Should anything ever happen, I then had a safe V2 speed at hand to accelerate to if desired with certainty VMCA would never be an issue."
I am struggling to find a performance calculation with varying conditions and weights where there is a difference between V2 at either FULL or ATM more than a knot or two. In most cases its the same.
Acknowledging my inexperience on the aircraft, am I missing something?