Martin Keller has now published a report about his achievement on his own blog. He's sharing his inspiring experience with all of us "silent warriors"! ;)
The new line is called "Der mit dem Fels tanzt, 8C".
Martins comment to the grade:
"And before i forget it, here is the grading-candy: for me the difficulty of "der mit dem fels tanzt" can be best described as about a 4-move-8B/B+ into a 15move 8B (or a 7move 8B+ into "einfisch/keinfisch 8A+/B"). the 6m-6A-slab-topout just adds some spice, but no real difficulty ;)
Compared in difficulty to a classic 8B+ like "the never ending story" (8A/+ into 7C+) in magic wood, this is another story. so when you want to use grades to express differences in difficulty, the only grade that makes sense for me is 8C."
keep on rockin'