I liked your description of the anti-shudder valve closing...new exactly what is was just by the "EEEEEEEEEEEEEEE-EEE-EE-E"
I guess the main question for a lot of people (including) myself is what is considered frequent and firm application of the accelerator. All the time? 3 times a day? Once a day? Once a week? Maybe once or twice per tank?
By no means am I worried about doing this - enjoy it quite bit, and love those free way onramps

. As with all things, too much of a good thing might not be good. For my driving style I try to do it when the opportunity presents itself, although won't take every opportunity. Just today we were driving around and didn't have a chance to wind it out. No big deal, there is always tomorrow.
For the record: When cold I shift around 2500RPM and accelerate gently - when warm I shift around 3000 and accelerate normally meaning I don't let it sing to 3000RPM and I don't make it roar to 3000RPM on a regular basis, something in-between that I consider normal. Just my .02.
To the OP - enjoy your car and I hope it gets sorted. BTW - what do the fuel lines sound like?
Also, as far as a TDI and the Autobahn? Pure THRILL! Drove a 2005 or so A4 2.0 TDI 6-speed manual in Germany - that thing was a blast! Wasn't breaking a sweat at 220km/h (130MPH) and routinely cruised at 160km/h.