Actually you have evidence of that? Cause I don't believe that for a second. I was a member of the ADC at that time. And I don't remember seeing ANYTHING about a iphone (this was before it was renamed to ios) dev kit.
But my email was full of guidelines to create web apps for the phone. What I think happened is that (at that time) Apple wanted Mac developers to make iphone apps, badly. And mac dev's wanted to do it natively. A half a year later, I see the beta of the dev kit.
I doubt Apple imagined the app store market at that time. And like most grand success stories, there was a lot of luck involved.