I'm in the habit of updating posts... people don't do it enough when asking for solutions.
Just wanted to post an update, after about 200km with the Porsche fluid, AND a new BAD shifter, the transmission is very slick.
It's hot around here, so that may have a little to do with it, but it's been getting progressively smoother by the week. Now, it's delightful. Almost no effort to snick into any gear.
I'm wondering what the reason would be for a gradual improvement..... I can only think of two things- A) There was some sort of glazing on the syncros that has gradually cleaned off under the proper fluid. Or B), The fluid itself has changed in some way, either more or less friction.
In any manner, things are good. Interesting.