Oh NO, do NOT skip Grenoble!! Or rather, the area just south west of it. Known as the Vercors, it hosts some unbelievable roads, places and scenery, that are amongst the "must-see" places on the globe!
You mean like or OK - I cheated on the last one. It's closed to traffic and bypassed with a tunnel now
Gotcha covered. Gorge de la Bourne. A major re-surface was underway during the summer so this section was closed, except for two weeks. I lucked it. http://www.youtube.com/watch?v=M70r3gf-7X4