My first question would be, if you probe at the fast feed rate and get a setting and then manually override feed rate to a slower feed rate and probe again, do you get a variation in the setting? If not, the feed rate change would only be to make you more comfortable and does not effect the performance.
As mentioned before, the 2 hit scenario probably does not save a value that effects the final output setting. It only gets a position to probe to at a slower feed rate. The slow feed rate probing actually captures the position for setting. In this case, see above.
If the 2 hit scenario is averaging, then it may be of value, if you do obtain a difference between the first hit and the second hit.