I think the main point here is - fast road driving is about making progress with a focus on smoothness, reading the road ahead and being safe. Same in a car as on a motorbike. On a typical B road here in the UK, a fast drive for me in the Peaks involves very little hard braking at all, so brake fade through extreme heat is completely unlikely. Hard and late braking is something racing drivers do as they are either on the throttle or in the brakes, no in-between. So this modification is completely pointless for fast road driving, it may however be appropriate for someone who tracks their car every weekend and has upgraded their brakes and still finds they get brake fade. To put simply, you can't drive hard enough on the public road for brake fade to be an issue in the GTI and if you do, you will soon end up either banned, crashing or dead.