I'm not sure it's really worth arguing about, but here's an anecdote from my last (until I switched jobs) 17 mile commute. I would ride for about 5 miles in either direction on the A90. The road is a 40mph single carriageway but with two lanes in either direction and it carries a constant stream of traffic, including buses and lorries. Streetview
here and
here.
When I first started, I was relatively timid and rode, a-la Jimbo, in the gutter. My theory was that by minimising how much I was in the way of traffic, I would maximise the amount of room I got and have to worry less about being creamed by close-passing HGVs and buses or left-hooked into oblivion.
Safe to say this was a disaster. I wasn't ever actually knocked off but I was brushed past by 40mph traffic more times than I'd care to mention. Traffic streams passing me would just turn left at major junctions as if I wasn't there.
The closest passes were rarely from the first vehicle, but quite often from the ones immediately behind, because the leading vehicle didn't obviously move around me so they had no idea I was there.
The big breakthrough came when I rode out with a more hardy cyclist who, although he had little experience of the road compared with me, immediately positioned himself in the left lane such that there was no way a vehicle could get past without hitting him. Not in the middle of the lane, just wide enough that there was no way to squeeze through.
What a transformation!
Suddenly, traffic was changing lanes before it got to me, people about to turn left were waiting behind me, and the number of uncomfortable misses I suffered dropped basically to zero. Only the deliberate buzzes remained, but they were rare and, crucially, it's much nicer being buzzed when you have some road space on your left instead of already bumping over yellow lines and drains!
I strongly believe that it is dangerous to ride in the gutter and more to the point, that encouraging people to do so is to put them at unnecessary risk. Yes, you can be hit by someone who has a brake failure - but even if 1:10,000 cars had brake failures that is fantastically better odds than 1 out of every 1 car coming close to knocking you off because they just don't need to pay attention to this bottom-feeding, gutter-hugging figure approaching in the corner of their eye.
Sorry Jimbo, nothing personal but while I'm 100% behind ideas like, pull over to let people past and make everyone's day, I think riding outside vehicles' "roll path" is way more dangerous than riding in it.