Tim Streater gurgled happily, sounding much
like they were saying:

If I'm stooging along the motorway at 65, look in the mirror, and
decide to overtake as the klod behind is a long way off, my
expectation is that he will still be a long way behind after I've
moved to the fast lane. I don't expect to find him up my exhaust
because the **** was doing 110.

If you're "looking", but not for long enough to gauge their rate of
approach, then you're not looking properly.

There is that, but if their rate of approach is low you may have to look
for too long.

Umm, you'd be able to tell their rate of approach was slow enough not to
be an issue, wouldn't you...?