Could be a very significant stage but then again it might not be. Stage 16 in 2010 Bagneres-Pau was somewhat similar but without the mountain top finish and that ended with a breakaway group of about 8 riders inc. LA getting to the finish nearly 7 mins ahead of the peloton. Didn't make any difference to the GC.
I'll be watching it live but then I don't have to get up at 3:30am.