Would this make a difference in chances of getting into surgical residency

This is for a bit of creative writing. People seem to think it's applicable to me (oh I wish).

If a doctor has a completed residency in emergency medicine, and has worked in a hospital for two years after the fact, would it increase/decrease/make no difference whatsoever his chances of being accepted into a surgical residency (since he chose to switch from EM to surgery).

Also, when you complete a residency, do you get some sort of degree to show that you have or entry in some type of database available to educational programs and employers?

Do doctors take the medical board exam before or after residency?

Lastly (yes I know I've gone completely off topic), do doctors carry ID to show they are an MD in times of emergency, such as at the scene of an accident? Or do people just kinda take their word for it?

Thanks so much if you can answer it all :).

Prior ER residency and hospital work may have a positive effect on your chances for getting into a surgical residency. You get a certificate of specialization once you complete the residency. Boards are taken in 3 parts: after 2 years medical school, near the end of 4 years of medical school, and near the end of the residency. Doctors have a license card once they get their state license, but I have never had anyone ask for it in an emergency. They just believe me (I look honest and competent).