Ok...in a residential 200A service, if you add up the breakers you can have well over 200A. I realize that not all the loads are on at the same time which is why the main doesn't trip...but how does one really KNOW if the service can handle all the ciriuts..and is this information found in the NEC??
Also...as far as subpanels go....what's stopping me from putting a 100A sub at the end of the house opposite the main panel? and then adding another 100A sub in the garage for a welder and other shop machines?