For the record (is anyone keeping a record?), I had a very similar thing happen one time. It was in a public toilet, not an ABS, so it was a little worse ... the last thing that I wanted was someone coming in while this guy was all over me. I ended up doing the same thing (minus the coup de gras kick).

I truly think the guy was nuts ... I tried several times to give him the benefit of the doubt, but sometimes you have to make your point (and to extricate yourself from the situation). The next guy getting groped/grabbed/semi-threatened may be a kid. At some point it pretty much becomes rape if you keep saying 'no', and the aggressor keeps groping.

Just my opinion. I probably would have advised anyone else to handle it differently, but it's easy to be objective when you aren't the one feeling threatened.