^^^nice post. From my experience, a 235 wide tire is pushing it on our rim. You end up getting "quench" to early then roll over on the tire, that is hard on the tire. You want the quench to be at its max point of flex, it is then using the sidewall the way it was meant to. Look at any race car that is setup correctly, we can always find pictures of bad examples, the tire is usually flush or within 1mm width per side, there is a reason for that. Yes, a 235 will fit, it has been done, and they may handle better in dry when normal non-spirited driving habits are being performed, but push that same tire to a evasive manuver, and it may not be good. The same goes for streching a tire, the sidewall is allready flexed, the quench is done, that is why some drifters will run rims the width out of the tire spec, this has not been proven to work, but they think it gets them to slide easier. I saw first hand what can happen, tire pulled off rim, car slammed into other car. There are reccomendations for all tires to rim width ratio, but remember, you should stay within 3% diameter, especially on a auto trans, and with 5% width. Do the math, 215*1.05(5%)=225.75(225width) or 215*.95(-5%)=204.05(205width). As stated above, there are tire designs made with the correct section width of 215 or even 225 that has a broad shoulder design to give more contact patch and still be in the correct parrameters and dimensions for saftey and handling. Also, not all dealers are bad about this, but usually if you go outside the parameters of the stock size, they will not perform warranty work on your vehicle, I had to take off my 20's because of the 245 width even though its on a 8.5" rim, my mechanic is a friend and told me to no show up with them on, they will void my warranty on my drivetrain, thank god bob came to the rescue with $50 element steelies with worn badyears, saved me the headaches for sure.
Sorry for any spelling mistakes, I have been up for 18 hours and just worked 13 of it. I am going to bed!!