I just had my new tires mounted on my 2002 SLK32 AMG last week. Prior to this I had heard stories of guys smoking their tires and such. Well I tested that and left a black streak 30-40ft. long in the street and I also left smoke that was as high as the street poles and it followed that black streak that we'll call 35ft. down the street. I have never seen such smoke from spinning tire as I did that day and it was from my car! Usually it is some other car that does such a thing.
Sitting in my living room were a pair of 255/40-17 TOYO PROXES R888 road race tires that are D.O.T. legal. At my sisters were the fronts, a pair of 225/45-17's. I called the Tire Kingdom and made an appointment to have these tires mounted.
Well I'm no baby when it comes to pushing my car but my fear to push the tires has yet to overcome the adhesion these tires have on the roads where I do most of my driving! These tires stick! You even listed the extra size I went with on the rears also. This gave me the first opportunity I had to get under the car and check things out. The rear set-up even had what seemed like enough to install a wheel with the width an extra 1/4" extra both inside and out. I love the look of wide tires on my cars but they must fit in the allotted space given by the engineers of the car. My all time favorite is the Porshe 911 turbo that has the rear wheel wells designed to hold whatever size tire that fits them, great look! Thanks for the thread, Mark
PS: I can no longer smoke the tires!

A taller tire with a patch that is long rather than wide will create better traction, another study for the physics class.