Trust me, Lance uses the 11. Many folks just don't get how fast those guys go on the flats, especially with the tailwinds. But when he first started, 52-53 x 12 was the top gear for most pro's and they went waayyy quicker than the average 11 cog owner these days.
Your average club cyclist basically wastes having 53x11 and 12. I'm a 185 lb. cat 1 and my top gear is 53x12. In years past it has been even smaller, 50-51-52 x 12. When the heat is on your not looking for more gear, you are looking for more speed, so typically the rpms go up. I could race flat NRC crits or Belgium kermesses with basically two gears, 53 x 14-15.
Now the sprint is different, but I still believe most sprints should be done on 53 x 12 or 13. The 11 will just get bogged down unless you are Boonen.
Last point. If you take an 11 and don't really use it, then you are losing another more valuable gear, such as an 18 or 16. Gears like that will get used often and enable you to keep your cogsets tighter.
My gear choice these days, 53 x 44 (12-23 ten spd)
My wife, an average club rider 50 x 39 (13-25 nine speed)