Saw at least 4 bikes - all of them 250s as it happens, which may be causal - sitting 2m off the back of cages at 110 on the way up the M1 this morning. One happily sat in my blind spot (I was caging it) in the same lane for quite a while... 2 seconds would be good, 3 seconds better. At 110, which is just over 30 m/s, 2 metres is 1/15th of a second, or about 0.07 s. That's how much time these guys had to react... and given that MotoGP riders have reaction times around 0.1 s... these guys have zero chance of doing anything useful if something unexpected happens. I know, there'll be plenty of people who say it's their choice, and it is. It's just a spectacularly stupid choice.