Dr. Awkward said:Well, even in a game like Dunjon or Runequest characters have to rest once in a while and recuperate after they've been attacked by the Evil Minions of Nastiness. So why not provide a guideline for the adventure designer that tells him how far apart to space the lulls in the action? It's not a D&D thing. It's a "oh my god I can't take another step, but now we have to climb Mt. Doom?" thing. Even if the intention is to push the characters to their limits, you still have to have a decent idea where those limits are going to be. Playtest data, translated into a CR/EL guideline, provides you with the means to make an educated guess.
I can understand your point of view as a 3.5 player. But in those other systems you listed like Runequest the whole EL is just not needed. the types of things you talked about are just obvious during play.
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