Level-scaling works in mysteriously annoying ways. Level 35 Seti = crapload of health on Camoran coupled with his equally (in comparison to my own) impressive grasp of restoration magic. The result is that neither of us die but continue attacking and healing ourselves... resulting in a never-ending battle... except when our items break. My sword broke and if I can't deal enough damage with my sword, how could I do so without it? It's also not like Camoran has armor or a useful weapon to break, so the battle would just drag on. At that point, I turned down the difficulty and finished him off.
This.
I was a pure mage (level 32), and my attacks weren't doing squat, if I'm right, he had spell absorption and spell reflection, and that made him a pain in the [censored].
I tried 5 times to defeat him, after throwing my controller in rage, I just set it to extra easy, then killed him.
In a more linear game I might, but given the nature of Skyrim's open world, no. There's always some way to survive or escape, and if it comes at a massive cost of resources (consumed potions, damaged armour, etc) that's just another, fun dimension to progressing my character.
There really was no way for me to defeat him. I had to defeat him or I couldn't do anything else in the game.
There isn't always a way to run or fight, sometimes you just end up in a crappy situation.