just curious - why a 2 piece propshaft on quattros?

[Livolsi, Stephane]

Just looking for anyone's ideas why the propshaft on quattros are 2 pieces
with a center bearing.  The position of the tranny and the rear diff are
fixed and don't move (much) relative to each other.  Why would the shaft
need that center support and joint?
I only have my 86 5ktq for reference - are newer quattros also 2 pieces?
It seems to me that the propshafts in north american front engine/rear drive
vehicles are longer than the quattro shafts, and I have never heard of them
failing (except for 4x4's doing crazy stuff)...

Stephane