Risk assessment of assertive cycling

I did have a trainee who got beeped at while we were riding; we were practicing taking the lane at road narrowings and a taxi driver didn't like it. She was surprised when I told her I was glad it had happened: because it showed her that being beeped at doesn't hurt and looking back at the part of road where it had happened she could see that, had she been by the curb, the impatient driver would have squeezed by her in a much more frightening way. So taking the lane worked for her and being beeped, while unpleasant and annoying, is harmless.
It also helped that it was a situation where the driver clearly had nothing to gain so the trainee could see that the fault was all his, he was the one being a jerk and from that she could, in a paradoxical way, take confidence.
I've also had a couple of trainees assume that a driver using his horn was beeping at them when they weren't; which is also useful too as you can talk to them about the assumptions they are making about drivers' attitudes.

Absolutely. When you get honked at, you've got a reaction. You've been seen. That's not a bad thing. Smile and carry on.