When I had my recall performed, I got the SA to print a copy of the Technical Service bulletin for me (not sure if he was supposed to, so no names to protect the innocent). This quote might help the discussion:
"Under certain driving conditions, the High-pressure (HP) EGR valve may become restricted with excessive soot. This restriction impedes the emissions performance of the HP EGR valve."
"An optimized EGR valve has been develped to limit this soot buildup."
Interesting that what BMW wrote seems to be contradicted by what TDIwyse is finding.