Umm hmm, I'm guessing there might be some conjecture going on here. It should be universally agreed upon by everyone that studies these things, that while adjusting the slider from minimal, braking ability increases to a point then reduces. The mechanical reason for this would be simple; you couldn't generate "brake induced oversteer (or understeer)" without breaking traction at one wheel pair. The only possible way you could generate "brake induced oversteer" (kind of like a built-in parking brake) is the same way the E-brake users do it, by breaking traction at the rear so it slides through the arc of the turn thus lining up with the exit. So, to set brakes higher than optimal would indeed reduce braking ability, but at the expense of actually overwhelming the ABS (Anti-lock Braking System) which would cause the rear tires to slide. Have you actually measured the amount of tire you save by INCREASING the brake slider? I didn't think do.
A similar condition applies to the camber settings, but I think for a different reason. I stand ready to be corrected on this, but by my understanding, wheels are canted or "cambered" to compensate for an arc-like loading of the suspension, in such a way that when the car is fully engaged in the turn the contact patch is as square and laterally supportive as possible. The converse being that the car is not as well linerally "supported" while on the straightaway (imagine the car riding on the inside corners of its tires because they are canted like this: / \ ) which usually isn't a problem since there is only one starting line and few Grand Valley style straights where you have to clamp the binders before stuffing it into the turn. This "ideal" or optimal camber should change as one makes adjustments that change suspension travel,
but it doesn't. It is developing (at least in my garage) that each car has an optimal camber that is as fixed and unique for it as it's name.
Furthermore, the GT4 physics engine does not distinguish between a straight line contact patch and a cornering contact patch. I discovered this through extensive testing using the first straight at Deep Forest. I found that, while adjusting the camber toward optimal (increasing), braking performance
improved. This is counter-intuitive and to me implies the physics engine doesn't actually model the suspension, it simply adds and subtracts values and when your "register" reaches a certain value, it dumps your car into that dynamic.
Additionally, I have seen no evidence of increased tire life while running the same extended race with a car set with less camber (or toe, for that matter); indeed, if you are sliding less on the straights, it is entirely possible you are sliding more in the turns. Again, I think the idea of saving tires through less than optimal camber is conjecture.
I would say you have done a very good job of nailing the ideal suspension response, the car sticks very well.
I took our Merc to Nurburgring, because it is pretty much the only place I drive these days, I'm learning all the turns. I chose Family Cup and left the slider at default. I knew your set would bottom at Quiddelbacher, but decided to try it as provided. My first impression was that it was even harder to turn than my sluggish set, but it held the road very well, in fact, my run consisted of brilliant snatches on the pavement interspersed with much "truffle hunting". It was pretty hilarious, I would come zooming out of the green, hit the pavement and hook-up, smack the Cien or Speed12 and send it spinning, then hit some bump and go careening of into the fields again, all the while pretty much hanging with the somewhat shattered pack. I left the last of them at the Breitscheid Bridge, the one over the small village at the cut-off to Bonn; and by Karousel (the first concrete hairpin) I had 2 seconds on the pack.
My more boring set turned slightly better, but did not bottom or upset when I would hit the rumble blocks (I am much better at tuning than at driving
) and by the Breitscheid Bridge I had my 2 sec's and by Karousel 6.
Bottom line is that I think balance trumps suspension acuity in GT4, but maybe I'm just a poor driver. I find that my early tunes handle the road very well but don't go fast for me, but when I "balance" the settings (meaning make front and rear similar) they handle maybe a little worse but go faster.
. It's fully modified with the best parts, including the rollcage, without nitrous, and uses Sports Medium tires. It also gave 1'09.702 on Midfield. 
