There's also the issue that most people don't seem to read (or at least remember the rules) The NASA rule is:
In most cases, “racing room” is defined as “at least three quarters of one car width.”
Though I've never understood why you'd write a rule for club racing that basically says it is fine to put someone two wheels into the dirt. That seems to just be asking for trouble.
And here's the rest of that rule that folks don't bother reading that says it is NOT ok to PUT someone two wheels in the dirt:
"The main purpose of the “¾ car width” rule is not to allow one driver to “squeeze” the other driver. The main purpose and intent is to alert the mind of the driver that is contemplating a pass that he/she may be “forced” to go two (2) wheels off-course to avoid a collision."
In other words, if you're making an aggressive pass attempt and there's contact and you didn't use all of the track plus a little more to avoid the contact, you're at fault. However, if the other driver INTENTIONALLY leaves you less than a car width of racing room, that driver is most likely going to be found at fault. At least that's how we run the show up North...