Why you should always assume the driver has not seen you

Assuming a driver will not stop has saved my ass so many times, and to think otherwise is ridiculous.
Trust he will stop ? or trust the driver to indicate and assume he drives completely error free ? No, you don't do that, it's something you just don't do, if you want to survive that is.
Preparing yourself on the "assumption" a car will pull out is pretty standard stuff, and like i said, it's saved me many many times.

Eye contact is optional

I suspect we are actually thinking the same way. It's just that I wouldn't say "assuming a driver will not stop". I would say that I don't assume he will stop; and I have a plan B if he doesn't. I think it's the same point but I am wary of the word assumption being used to describe what is actually, in both our cases, a fairly sophisticated approach born of experience. What you are describing, and the approach I advocate, is much more 'active' and thought-through than the word 'assumption' gives credit for. Certainly I never go on 'trust'. I really think we have the same view but maybe semantics has confused it. Also I think I know a little about how to survive cycling in London :)