Suite to Master or Slave cylinder question - I have no clutch now

[radek at istar.ca]

Hello listers.

Thanks to all who responded yesterday to my call for help on the master/slave cylinder
question.
I checked the return spring - it's OK.  I have enough fluid in the reservoir.

The clutch failed on my Typ 89 a short time afterwards. On my way from work I had to shift
clutch-less.
Actually, it's not as hard as I thought, the whole trick is not to get stopped. As long as
you are moving,
shifting is easy.  Not a single crunch all the way but I came close to running a couple of
lights.

My problem now is this:  how can I tell which part of the system has failed?
My friendly local parts dealer insists that, based on the symptoms I described to him,
it's more likely
a failure of the clutch mechanism itself (e.g., a realease bearing sticking) than of the
hydraulic system.
To confirm that, I'd have to remove the transmission (no, not today).  So I hope I can get
some
diagnostic help from the group, please.

Here are the symptoms:
First, the clutch pedal would not return fully (would go up about half of the way).  If I
pressed on it,
there would be resistance  and the clutch would operate normally.  If I lifted the pedal
with my foot
to the normal position, it would stay there.  If I then pressed on it, it would be "empty"
half way and
then I could feel normal resistance.

The second thing than happened, the pedal started returning less and less, untill finally
it would not
return at all.  No clutch.  When lifted to the normal position, it would stay there.  When
pressed, there
would be no resistance all the way to the floor.  Actually, it felt like something was
pulling it down,
like vacum or suction.

After remaining undisturbed for the night, the pedal would again show some weak resistance
when being pressed but only for the first time.  The second time I pressed it there was no
resistance
again.

So my question is:  what failed?  Any hints?  Should I be buying a new master cylinder,
slave cylinder
or a clutch kit (the clutch was replaced by PO about 60k km (38k miles))!

TIA
Radek
88 90Q
91 V8Q 5-sp.