Can I run a different tire diameter in front and back? (2014 RWD)

There's a lot of posts in various forums saying there's no problem running a different tire diameter in front and behind (2014 RWD), but some posts claim that it messes with the ABS/Traction Control because of the different rotational rates. (talking about a 27" in front and 28" in back. assume I've re-tuned to the size of the rears.)

Anyone know what the real answer is? Just from reading posts I can tell there's a lot of people running different diameters but IS there something to be said about ABS/Traction Control?

Why would ABS/Traction Control NOT be affected or is that not how it works? (...because I don't know how it works.)
 
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The real answer is that the car is a rolling computer system. Any modification that pushes the car outside of a measurable performance specification will trigger an issue with the PCM.

This has been true since 1986. The only difference now is that the computer systems in these cars measure more 'things'.

ABS and Traction Control are two different things so the answers would not be the same.

A very general answer would be: Any modification that pushes the car outside of a measurable performance specification will trigger an issue with the PCM.
 
Thanks, but that doesn't get me any closer to a practical decision. Another way to phrase it relative to your answer is am I going to see a warning light for either the ABS or Traction Control? I'm sure the answer is going to be there's no way to tell at this point.

I know there's people out there running different sizes so it must be possible.