Seat TPI2017192/1 - from my experience with this
problem, the "fix" mentioned is more of a work around - rather than a fix. All Seat TPI2017192/1 does is pass the
problem on, by filling up the doors with water.
Cutting off the front few inches of the
lower window seal doesn't say much for the design / effectiveness of the seal, which I would assume was to keep water out of the door internals (wiring / motors & speakers etc).
If you look at the shape of the
lower edge (front & rear) of the window glass, you will see that it is not flat, but has a raised
lower edge, meaning that the water in the outer window seal, shoots under the glass, and onto the inner window seal - hence the wet windows inside your car.
I had mine "fixed" with TP, only to have damage repairs done on one door, when the repairer refiited the new parts, the
problem returned on that side 'cause the window seal was a non-modified part.
It is a shame - because it's a great car in most other respects!