So heres a thought....
 

Lets just say Lance gains a few seconds back in a TT and regains the lead until stage 20. Does Contador ride as cover for the yellow jersey on the final climb and vice versa.

I guess what im saying is if Astana has the race pretty much locked up before stage 20, does stage 20 lose its luster? Will Johan let a member of his own team challenge for the yellow?

I doubt at that point if it anyone's decision besides Contador's. I suspect he will go for it. When he said he attacked because GC threats looked weak who was he speaking of? I suspect it was Lance. If you notice when Evans attacked Contador had to close the gap.

Richard