Let it not be said that I didn't love driving any of the Pawnees .. all great fun. However, the little one didn't leave much to spare on a gusty, bumpy day with a two-seater on tow. At one field, where I was wont to tow many decades ago, I recall that only a couple of us were interested in towing in the little Pawnee .. the others preferred the Super Cubs... mind you that all changed when the little Pawnee was exchanged for a bigger brother.
I'm surprised that no-one has mentioned the Callair .. similar to the Pawnee and, stripped down, a really good tug .. especially when operating from a military aerodrome where one was not quite so constrained in respect of circuit procedures during the recovery. However, I always found the near total absence of aileron control a tad disconcerting during manoeuvring onto short final.
Shock cooling has always been a worry with tugs (and on parachute operations). While I have no recent knowledge of what is done, going back to the 60s/70s it was very apparent that those clubs which used fewer pilots and exercised reasonable control had fewer problems .. largely due to the better training and operational controls which could be exercised.
84 aerotow launches
Good Heavens .. I had a few excellent days but I don't recall ever getting over the 60-odd mark. Ian must have had one unbelievable boomer of a day with a majority of quite low releases ? He would have been one very tired little teddy bear that night ...