In a real-time RPG combat should be real-time. Don't mix the two, it just kills immersion and breaks the flow of the game. Disliked it a lot in Final Fantasy games when you ran around the map in real-time and just wanted to get from Point A to Point B, and all of a sudden there was a transition effect and you had to fight a turn-based battle.
{/my personal opinion}
As for the stealth in Oblivion, considering that the rest of the game was as unrealistic as it was, I guess we should be happy with what we got
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