Is it time to start calling out bad cyclists?

I was filtering down the outside of sloooow moving traffic approaching some lights on Mile End rd just now. There was a behooded Borisenger in front of me centre lane. No shoulder check, he suddenly accelerates and pulls out to overtake so I say "your right mate". "What you sayin" comes our chirpy response. "I'm on your right, watch your line". "Fuck off then you cunt".

Lovely!

Too polite. Just say, "Do that again and I will end you!" Then ride off.