Disregard?
In general, no. I try to be aware of the traffic laws and obey them if they make sense. When the traffic light is red and cars are whizzing by at 60 mph in a 40 mph zone, it makes a lot of sense to wait for the green, so I do. After it goes green, if there's still cars going by, the law says I can go... but I still wait until it's safe.
My basic rules are : Don't get in the way and don't annoy anyone.
I concur with rhm.
In general, no. Actually, I'm used to say that "I drive my bike". I just pretend to be a slow moving car, and act accordingly.