Noone said "weight has nothing to do with braking distance".
Please read and understand the technical details given, especially at the beginning of this thread and in this article:
http://www.miata.net/sport/Physics/07-Circle.html
Instead we say: The tires of a vehicle give the upper limit for the maximum possible deceleration, and this limit is
independent of total vehicle weight. (There are second order effects like weight transfer, temperature and so on, but let's put these aside for a moment).
To quote from the article:
This means, for instance, if you are not satisfied with the braking distance of your modern sports car, it would NOT help to
a) equip "stronger" brakes
b) reduce vehicle weight
What you could do is
* get other (better, gripier) tires
* try to increase braking performance by looking at other things, like weight transfer, center of gravity and so on.
"High performance" brakes do not reduce braking distance, instead they give better "feel" when braking, reduce fade and operate better at higher temperatures such when making heavy use of the brakes (i.e. driving curved downhill streets for long distances).
Click to expand...