Hmm, my interpretation was similar, but just a little different, maybe not quite as concise as yours. It's more of... you stupid thing, we could have had it great, I would have given you the world. But, like you said, he was unwilling to commit. I think you could easily read into this song a guy who got what he wanted (i.e. getting laid), but wasn't willing to make the emotional commitment (it wasn't me that you outsmarted) and cheated himself out of the real prize (a meaningful relationship).
Hmm, my interpretation was similar, but just a little different, maybe not quite as concise as yours. It's more of... you stupid thing, we could have had it great, I would have given you the world. But, like you said, he was unwilling to commit. I think you could easily read into this song a guy who got what he wanted (i.e. getting laid), but wasn't willing to make the emotional commitment (it wasn't me that you outsmarted) and cheated himself out of the real prize (a meaningful relationship).