I went on with this much longer than was necessary or sensible.
I did, however, satisfy myself that most people who write about Heidegger are being very... selective. One of his core beliefs is that (in the modern world) only Germans comunicating in German can be authentic - which makes the H. cult in France especially bizarre.
But H. does offer a self-gratifying fantasy on the vital importance of academics to - well - everything. A very elaborate, ponderous, erudite, serious fantasy - retreating to the silence of a hut in the Black Forest is so much more respectable than dressing-up as Dumbledore...
Even after I had satisfied myself that there was nothing there but pretentious platitude plus error, I went back again to sort out the Nazi question - about which there *seemed* to be some disagreement or confusion.
But that really is very simple indeed. Heidegger was a lifelong, unrepentant National Socialist, and that is all there is to it.
It is only a problem if you are a modern academic who affects to admire Heidegger (if the academic is non-German this entails not understanding him, by H.'s own assertion) - yet being an academic, the typical modern Heideggerian is a typical PC lefty.
(Richard Rorty was an example of the combination - he did not understand Heidegger, he was a PC lefty, and he ignored the Nazi business. Yet if Heidegger was such a great moral philosopher as Rorty said he was, then the fact that he was a National Socialist is... interesting, surely? In an *obvious* sort of way.)
But this is not really a problem, since PC leftys are intrinsically dishonest - therefore it is facile for them to deny or forget that Heidegger was a Nazi.
Hence the persistent pseudo-confusion on this matter. But, really, it is not worth the time or energy of sorting it out. My advice: Don't bother.