The poster (mainehazmt) asked if he 'could' use non-standard repeater pairs, not if he 'should'.
The replies were that he can't because the rules say he can't.
All I was pointing out is I don't read that in the rules regardless of what they intended, nothing more.
Finding the correctly worded rule is a fools errand because it doesn't exist.
What I did find in CFR 47 90.173(i) is:
(i) In the 450-470 MHz band, the frequencies are ordinarily assigned in pairs, with the mobile station transmit frequency 5 MHz above the paired base station transmit frequency. In the 470-512 MHz band, the frequencies are ordinarily assigned in pairs with the mobile station transmit frequency 3 MHz above the paired base station transmit frequency.
But since GMRS falls under part 95 it wouldn't apply. If the FCC wanted to specifically assign 5 MHz offsets,
why wouldn't they word it the same way as they did in part 90?
Also, notice it said "ordinarily", which implies the rule isn't set in stone.
In any event, a part 90 frequency assignment would come via the recommendation of the local coordinator,
which GMRS doesn't have.
I completely agree in some urban areas where there is GMRS congestion that would cause an issue,
but for example where I am located there are only 2 GMRS repeaters located within 100 miles of me.
Looking up the posters callsign, I'm sure in Limestone, Maine there isn't a plethora of GMRS repeaters either.
So can we agree the answer could depend on your location?