Not at all.
He says when "braking hard".
Braking hard will emphasis any warpage within the discs.
He say's braking QUITE hard, hence the reason for my first question. then replies afterwards saying (after giving them a bit of stick and braking sharply).
if he has a warped disc it will be warped all the time, the warp on the disc doesn't go away once it's cooled down' it will just be more severe when hot.meaning it's more noticable when hot, the probable cause of this problem will be a build up on the edge of the disc that the pads barely touch, or a build up of corrosion on the middle of the inner side of the disc,