I said that backwater villages SHOULD have very weak guards and that the best guards should even beat you midgame IF they gang up the player. By the endgame your character is usually as powerful as a god, so obviously no ordinary human can stop her/him.
But it's not like Tamriel doesn't have semi-regular in demonic invasions, so I guess elite gurards should be equipped and treined for even that. So I don't think it would be outrageous for 5 of them to even match Dovakhin in combat. Obviously, this is the absolute top, the royal district guard or something similar.
Between the two types, there can be several others, most of them wouldn't kick your ass after getting 15 levels or so (in Oblivion's terms.)