Boy, here goes. I'm thinking I can't write what I'm thinking without pissing somebody off, maybe lots of folks so I'll shoot for maximum diplomacy. First, of course you should try to leave yourself an out at a stop. Of course you should have all the lights and reflectors, front, back, and sides, your bike and gear can carry. Naturally you should wear ALL your gear, ALL the time. Will some bonehead hit you anyway? It's damn possible, sooner or later. Will you get hurt anyway if he does? Pretty likely. Will you get hurt as badly if you're wearing the gear as you would if you're not? Probably not, usually. Do you improve your chances of avoiding getting hit if you leave yourself that escape route? Damn right, some of the time.
It's all about giving yourself whatever edge you can get and stacking the odds just a little bit better in your favor. We all hear the rules and the advice; some of us follow them, or some of them, some, most, or all of the time. If you can improve your chances at all, sooner or later you might save yourself some trouble, expense, or pain. That's the best we can do. It sure doesn't help anybody to say "this won't help" or "that doesn't work." If it EVER helps or works, then why the hell would you not do it?