Several years ago the question came up as to the original source of the requirement for a five second delay after the air/ground transition. Best we could come up with was "we've always done it that way
Could it be for that one time, when PF decides with wisdom, that attempting to stop with the little runway left is perhaps not the better option and spooling up and re-launching gives a 2nd attempt to get it right. Remembering the reason why engines are spoiled up first before selecting takeoff power, could this be to avoid any delay in them spooling up for the aborted landing case? Of course, once TR's are deployed all bets are off.