Basil
ZFT,
Unless your captain had calculated take-off performance from an intersection but actually commenced from closer to the downwind threshold (longer Take Off Run) then the take-off calculation is invalidated by ambling down the runway as you report.
There is always the possibility that it was done intentionally to check something.
I don't disagree with you. It may well have been something intentional. That's why I was deliberately vague about location and carrier. The point I was trying to make is that as a pax there is nothing you can or should do. (Personally, I doubt whether it was normal as there were a couple of other events just before the flight that did have me more alert than usual and I won’t be using their services again).
For the record it was a 12,000’+ runway and the take off roll commenced on the displaced threshold.