The refraction observations are interesting though, so it's not a total loss. I'm not aware of any similar illustration of total internal reflection of a laser over such a large distance. It's nothing new to science obviously, but a very nice visualization.
Agreed - a very good visualization of the mirage effect showing it clearly isn't a sharp reflection but a continuous bending.
I suspect your criticism of taking subsequent measurements with the boat moving is spot [pardon the pun] on. I thought what had been discussed was stopping the boat and taking a series of observations and marking the average on the board?
So the laser could easily be pointed down sufficiently to swamp the later measurements - pending additional details.