AGR Problems in the USA?

Regarding the ongoing issue of EGR systems and partial load: In the US, there are speed limits everywhere, for example, 80 mph, which is almost 130 km/h. At that speed, the engine is still operating under partial load, so exhaust gases are still being recirculated by the EGR system. The practice of 'de-throttling' on the Autobahn, which is common in Germany, is actually illegal there.

That means that US-market TDIs only have a closed EGR system during acceleration. Therefore, they should have a lot more problems than we do, us highway drivers. Does anyone know anything about that? (I haven't checked Fred's TDI forum in a while, unfortunately.)

Regards,
Robert.