As far as I know, the windscreen wiper problem has never been formally resolved. There is a TPI, 2013403/9 dated Dec 2009 but this does not address the Scirocco owner's experiences.

There appear to be 4 versions of the infamous smear.

1. Waxes and polishes, particularly nano type. The TPI refers to this problem only.
(Fix: Clean windscreen with Window Cleaner - part no. G 052 184 A2).

2. Deformed windscreen areas leading to shallow depressions which the wiper skips over.
(Fix: New windscreen)

3. Minute droplets of windscreen adhesive on the windscreen surface left during production assembly which gradually spread to ultra thin patches about 25cm - 40cm across.
(Fix: Remove adhesive patch ( polyurethane based)).

4. The Scirocco's plastic wiper carrier of the blade assembly which holds the wiper rubber itself collapses in the central portion under the downward force of the wiper arm, slightly squoshing the wiper rubber. This can be checked by bringing the arms upto the vertical service position and check the plastic carrier runs parallel to the windscreen at about a 6mm constant height above the windscreen surface. Measurement is not critical, constant height is.
(Fix: Fit Mk6 Jetta wipers part no. 5K2 955 426 (Driver side)/5K2 955 425 (Passenger side) which can be done as warranty items, VW (UK) used this after discussions with VW Germany. Or pay for your own, aka Bosch equivalents.)

I had 3 & 4 problems above. Had the Jetta wipers option on for 2.5 years now and not looked back.