Is it time to start calling out bad cyclists?

me:
this morning crossing Upper Thames St in front of a lone cyclist, dithering and neither going fast nor slow enough to let him pass comfortably, he calls out "helloooo!" slows almost to a stop, I mumble my apologies.
sorry bicyclist :/

Quite possibly this was infront of me. At the end of the day everyone makes mistakes I won't see certain cars, pedestrians or cyclists ALL the time. It isn't a case of bad cycling it just happens. If someone does something wrong once doesn't mean they're a bad cyclist. This thread reeks of self importance.