I think I can forgive someone using the language of their past self when reflecting upon that past. In the context of the paragraph, I think it's fair to say that "which worked" means something more along the lines of "and things did get better." Maybe he could have improved his word choice in that instance, but I don't think that negates everything else said.

I can already hear you saying "but that's not what he said, and that was his choice of words." And to that, I point to one of the key lessons I learned in college philosophy: questions of meaning come before questions of truth. In this case where one short two word sentence does not fit the rest of what he is saying, I think it's best to ask what they could mean that would fit.