Doesn't that same logic apply for the scat pack guys? Most people who are going to spend over 40K on a vehicle will want to add leather to it.
And the LS3/L99 auto record is 12.7@108, with a better 60' than Kelly had. I don't see them picking up 4 mph and .1 with a worse 60' in a worse DA by dropping 120lbs but filling the tank with 115lbs of fuel..
And as for the progress thing, just poke around, read what the guys who have driven this car have to say. Motortrend made it sound like it has no improvement but everyone else absolutely adores this thing.
Close but the L99 running 12:70s was running stock rubber. Do you not think that the addition of lightweight wheels and DRs would not give the car atleast another tenth or two reduction in E/T? The cars would be dead even. Maybe the times will get better for the S550 but right now it just doesn't look good.
As to the Progress thing, sure it drives better, handles better, and is more comfortable, but the things that really matter didn't improve enough to beat the competition. I think everyone in this forum was expecting more. Ford simply didn't deliver. Maybe they didn't want to show all their cards until the 2016 Camaro rolls out?