Is it time to start calling out bad cyclists?

it's not that amazing. if you're not absolutely sure when the traffic is going to start moving again, or the road layout ahead. plenty of cyclists simply do not want to be caught on the right hand side of traffic when it's moving, especially if they are slow. there's nothing wrong with dawdling along behind, in line with traffic.

I think you misunderstand me; they clearly want to get past the vehicle, are determined to undertake at the first opportunity and do not consider overtaking an option at all.