It's an interesting way to make people consider, and really think about "the path not taken."
It seems a shame that because of the time constraint, the absence of replay, and the lack of inst5ructions at the start further eating away at the time counter; that not all your story line can be appreciated and (or even completely heard.)
Personally, I'd allow for 2 extra play throughs. The first one really drives in the sense of every decision being final, and the half-hour commitment to a replay, just to get a sense of the overall storyline and artistic work, is enough "price" to pay for your choices.
I feel sorry for the people who chose the arc straight off, and didn't get most of the experience. Nor will they ever, unless they have a flash cookie editor.
Still, neat idea!