okmatewanker

In the UK, you're not meant to get within 6ft of a bike when you're overtaking it (although it's pretty common for drivers to get muddled and think that rule's talking about inches). That means it's not safe to overtake if there are oncoming vehicles in the opposite lane or solid white lines in the middle of the road. Another bike a metre or so from the first one doesn't change that if you've got to cross into the opposite lane anyway, and it's better if they're two abrest as you don't need to be in the opposite lane for as long.

There are plenty of idiot cyclists who endanger themselves, but there are also plenty of drivers who accuse people of being idiot cyclists when they're following The Highway Code to the letter.