Yes, being an ex-ping jockey, I know what cavitation is. :-) I heard enough of others boats' cavitation.
Also studied it in relation to the cavitation that smaller recreational boats suffer. I have owned many over my lifetime. :-) The good thing about smaller boats is that you can actually hear the cavitation when it occurs and you can slow down. :-) It can really eat up a screw in a relatively short period of time and, as you say, right out on the tips and vortex.
I backtracked his responses/posts by number and none referred to "cavitation" so I must have missed some of his other posts.
The original question was the same old question about why the sonar wasn't in use at 35 knots. :-)
I can't blame people for asking the question, but it does get tiring answering them thread after thread. One of these days I'll work up the energy to compile the links so these nice folks can find the answers themselves.