I wonder whether most of prophylactic effect of the described dipping process is simply due to removal of the base? I suspect that most nasties are removed with the base and subsequent visual inspection of the coelenterate's tissue. Do you folks see things actually fall off the dipped tissue?
If I see anything that looks like a bite or pest, I throw out the frag. Removing the frag plug is indeed prophylactic because it's difficult to visualize pests/eggs in nooks or crannies.
I find the dip is so opaque with Bayer that I don't really see anything in the liquid.