It seems to me you can't generalize about what people are planning on doing based on where they're currently employed. Maybe it seemed like a good job at the time or there were exogenous reasons to take it or they didn't know what the options were or whatever---the fact that the institutional structure only allows for a few kinds of advancement doesn't mean that everyone at the institution is planning on that kind of advancement.

The same thing of course applies in the other direction; you can't tell what someone's intentions are from the fact that they're using Clojure.