Deviation problems? in Astro systems

[rapier6360]

In a digital Astro simulcast system the deviation is supposed to be critical.
On portables and mobiles the Deviation limit is supposed to be 2.78-2.88. How far off of that number can a radio be before it starts having problems and what type of problems and symptoms will you see? Where can I find documentation on that? As usual Moto doesn't like to give strait answers.

FYI - if the reference oscillator is near 1000Hz off you start getting channel grant failures -bongs. I imagine if you combine that with an out of spec Dev Limit then the problem increases.