Yes, but as I indicated in post #73, the CSA never lasted long enough to see how that would work out, and I argued that even if they had lasted until 1866, Jefferson Davis would have likely been granted an "emergency extension" in office because the CSA was in no position to hold national elections and have a smooth transition of power to a successor in the Presidency.
Mexico is really the only nearby country where we can see the effects of a single 6 year term in office.
I won’t say RR had a bad second term (although I’m a RR fanatic, so my objectivity is very skewed).
One six year term for POTUS would be a positive development. Too bad we didn’t get to see it in action in the CSA.