Brake at 400m, use gears for engine braking, pray to whichever god you believe in, put up a sail, throw out an anchor...
...still end up cart-wheeling through some hay bails and end up in the river!
Sounds about right for when your brakes go over 700C. I don't remember exactly, but I think I have made it so that you have half of braking power when brakes reach 1000C, 300-500 is optimum window, if I remember correctly
Just searched for old Longford videos, oldest I found was 1958, where they presented that track has been improved. There is nice video from 1964. A bit too new

but you see people haveing troubles while braking, red jaguar crashed into a trees after wheels lockup when braking..
By the way, interesting thing with brakes fade. It is possible to get into situation when front brakes fade significantly, but rear brakes are still at or near optimum window. In this case brakes blance change obviously, and you can lock rear wheels if you brake hard. In this case you not only loose braking power due to fade, but you might not even be able to push the brakes to the macimum due to rear wheels locking. It might happen sometimes.
Disc brakes (that few cars have) aren't very much stronger, but because they have much better cooling, they don't really ever have temperatures issues.
In fact in some cases drum brakes can perform better if it is in the good temperature range, and if braking is not too long, so it does not overheat. While disc brakes could have possibly got too cool and you may have to brake for some time to put them up to temperature.
I have read about modern ceramic brakes, that they have bad fade whe nthey are cold and they need high temperature to operate optimaly, drum brakes inverted ?
One more interesting thing about braking. I actually don't remember if I have already spoke about these things, might be 5th time lol, nevermind... You sometimes may forget trailbraking with them (partialy or even completely), when fade hits it does trail braking for you at some level
