TF110, the track is the same width at Turn 10, and through the chicane, as it is everywhere else around the lap, except for the pit straight. The pit straight is 18m wide, and the entire rest of the circuit is a damn generous 15m wide! It only looks narrow because of all those corners!
(People say VIR is narrow, but no, it's fine as-is. Again, it just looks narrow because of the arrangement of the turns. It's 30ft (9m) wide, just like Road America, Road Atlanta, Lime Rock, Mosport, Mid Ohio, Laguna Seca, Sears Point, etc. Even Barber, a "new" circuit, is only 40ft (12m) wide.)
And the braking zone without the chicane will still be enough to work just fine; maybe it will be a 3rd gear corner, instead of 1st. The reduced accordion effect will be helpful as well in reducing congestion, plus that somewhat quicker turn will play more into the strengths of the LMPs, making it easier for them to pass there in that respect. Without the chicane, that designated braking zone will still be a heck of a lot more effective than the one designated for the last corner. Remember, kinetic energy goes up with the square of the velocity, so going from 90-mph down to 60-mph is nowhere near the energy reduction of going from 150-mph down to 120-mph, even though both are a reduction of 30-mph.
I've seen the crowd figures too, and in the Group C era, ~80,000 for the event was normal. Here's another good place for sportscar information.
http://wsrp.ic.cz/
Greg, that's an interesting thought about the length of F1 races. That leaves me with a question though. Why wasn't this thing going on with the tracks back in 2002-2005, when the races were faster, because of horsepower, and the cars weren't carrying so much fuel?