>It's inherently subversive of any central and stabilizing intellectual tendency and I think most critical theorists admit their goals as being such.
It's very hard for me to read that as anything but a good thing. It's one thing to say that critical theory has no value, but it's another thing to say its only value is subversion. Nevertheless, if what you're saying is true, then there is no better critic of critical theory than critical theory itself. There are central principles of critical theory (and Horkheimer wrote a whole book about it), and there are results produced by critical theory that the authors present as true (sociologists have taken up the concept of the culture industry and Marcuse's idea of one-dimensionality, for instance). I'm skeptical of the idea that CT is subversive of any tendency - no critical theorist repudiated empirical investigation, for instance. When they do criticize, they don't want to completely do away (Adorno had praise for the enlightenment project). Habermas has been one of the loudest voices against "postmodernism".
> productive operational work (in science in policy or otherwise) always has to maintain some initial set of working goals and assumptions to guide and rationalize action
That's true, but if critical theorists do not question these working goals and assumptions, and the very nature of instrumental reason, who will? It seems to make much more sense, for human emancipation and rationality, to examine what we take for granted and against what background we're working. "Maximally orienting towards further action" is precisely the uncritical approach CTs stand against, where in the same breath we guide the Ministry of War "maximally" towards "further action".
>no they're not worth taking seriously except as a means to an end.
Not only do professional philosophers of all stripes disagree, but career activists agree - a famous critical theorist (lowercase) once said that philosophers had hitherto only interpreted the world; the point is to change it.
>the problem of interpretation in foundations and the way they want to internalize Hegel, while still having the aims of scientific inquiry in mind
Scientific inquiry has many prerequisites, Hegel himself a harsh critic of pure empiricism. The difference in prerequisites is what gives rise to the Anglophone science and the German Wissenschaft.