As to all your 'What-ifs.' Ask yourself what is the worst that could possibly happen if you <whatever it is>. Most of the time the worst really isn't all that bad, can be dealt with or something can be done to avoid it. Or, you can have fun and see just how bad you can make your desired action. With practice, you can get commuting your bike to cause Armageddon - at least in theory.

The point is to get a pretty good idea of the worst possible risk, which is often something you can deal with, anyway.

It's a liberating excercise. And if you decide not to do whatever it is, you at least know exactly why.