Peter;
On a 170A its a question of playing the game, I personally would not go for a "rapid left right full control manouvre"; If you brief the examiner that you will carry out a full and free in seperate parts ie "as we turn left from dispersal I will check full left rudder and full right as we turn into wind for power checks" and highlight the reason why then he should not fail you if you have good airmanship/POH reasons.
I've just checked with FF and VH and when we did both 170 and IR power checks were carried out into wind (different from your other post, god knows why that has changed)
SND