Agreed, by definition any big power car on a circuit isnt ever going to see sustained load at one point in the rev range, as the speed is ALWAYS greatly transient at full throttle as you arent going quick enough for their to be enough wind resistance to slow your progress drastically through the rev range.
Different story in a 100bhp car on the bedford back straight of course, where you could easily be sat at near peak rpm for long periods of full throttle! lol