Test flying, is carried out by highly qualified pilots, with the technical knowledge to allow them to look for trouble. This can only be done with any degree of safety after hours of planning etc.
And the very
last thing a test pilot is going to do is horse around in an aircraft, incurring lots of risk for nothing more than showing off or a bit of excitement. It's a VERY career limiting attitude toward safety and professionalism!
Every test flight I do has a "risk/benefit analysis" portion of the flight test plan. Waterskiing a wheel plane would not even come close. When the analysis comes up with "high risk" and no reward - there will be no test flight of that.
Interestingly, I was speaking with a former US Army test pilot not too long ago. He described to me formal testing of several taildragger types on snowskis, waterskiing on water as a part of an evaluation. They did not continue this evaluation, for the poor risk to benefit. Hint there!