As I've said before, you get clowns in every road using community.
I'd rather hope as licensed Taxi drivers in London tend to do it as a career, opposed to an in between jobs number, they would value their living and not jepordise it over bust ups with cyclists or other road users.
As a Cyclist and a Cabbie, I see it daily, and I'm sure any Cycling Bus Driver will profer his opinion too.
My only real bad experiences tend to relate to couriers and their suicidal riding. Fixed, minus any brakes etc.