some people are when they move up in tire size. Most are not to my best knowledge. I would bring it in to the dealer to atleast have them look at it, if you know they wont say anything about your new tires.
It isn't tecnically the traction control causing the problem. It is the RSC and ESC. Which can only be turned off up to 35mph by holding the button for 6 sec. I hope Ford eventually has a TSB on this and allows the dealer to adjust the sensitivity of these features.
Just a thought, but is everyone who is having this problem check the PSI to make sure all tires are spot on where they should be? I'm guessing the RSC and ESC work off the difference in tire rotation and 2 or 5 psi difference in a larger tire would cause more of a difference in footprint/compression than the same psi in a stock tire...
theres gotta be a reason why some people are having more of an issue than others