On Saturday, May 2, 2015 at 7:46:38 AM UTC-4, Bruce Hoult wrote:

If it is merely a signal to the towpilot that has little to no actual effect on the towplane and it's up to the tow pilot to take the hint or not, then that is one thing. If it is physically pulled the towplane's tail around then that is quite another!

That seems to sugar coat what happens sometimes... To paraphrase my excellent and expert CFI-G... 'You really have to pull on the tug's tail and point him in the direction that you want to go.' And so, on more than one occasion, I've given much more than a subtle signal and I've not yet gotten a complaint from a tug pilot.

That said, I will going forward, use the radio in lieu of tail pulling. Maintaining optimal position behind the tug might provide a slightly better margin, especially on a gusty day, and especially if a tug pilot might react by releasing me at low altitude.

I still think that 'boxing the wake' (with the tug pilot's OK) on a reasonably calm day is a very good skill building exercise and that it is well worth the small risk above 1500 AGL or so.