Dear oh dear, so keen for a fight. 

Who said that I now appear 'certain' of my own contribution?

The fact that warts are susceptible to placebo disappearance and the fact that this particular disappearance coincided precisely with the time limits I suggested, coupled with the fact that the 'poor unfortunate' was himself convinced that I was responsible,  make me suspect that my action contributed.

However, I used the word 'contributed' to imply that I could not be certain that I was in any way responsible and the disappearance could indeed have been purely coincidental.