I'll admit I voted no.
But, perhaps for a slightly different reading. I read the question to mean, was the balance that 1e achieved arrived at by design. In other words, I took the design part of the question to be important.
It's pretty much true that all games are trying for some form of balance. That's pretty much necessary for most games. Allowing me to start with three aces in Poker is an interesting variant, but, not very balanced. However, giving you ten to one odds if you win, suddenly shifts things back again.
However, my thinking is that AD&D was not designed in the sense that we mean it with games today. Most of the mechanics were back of the envelope style calculations with an awful lot of gut feeling producing many of the numbers. At least, that's the sense that I get from AD&D. There was no design team to speak of, no rigorous playtesting, very little in the way of games theory being employed and so on.
So, how much can you really call 1e "designed"? To me, design implies a pretty formal, scientific process. I got the sense that 1e mechanics were arrived at more or less by trial and error and "close enough" was generally acceptable.