After talking a bit about it we went ahead and tried playing pair RRT.
These were the rules:
The players in each pair had to sit "across" from each other (on an imaginary round table).
To determine the winner then lowest of the two scores for each pair would count.
Other than that normal rules would apply. The pairs could discuss strategy as they wanted, but could not reveal their tycoon, and we decided that it should not be one player playing for both, but no hard rules on that.
It turned out to be an interesting game. I dragged on for quite a while, because we we all trying to figure out what was good or bad strategy. We might play it again, but would definitely change it to sum of points, because trying to balance the points within each team proved to be one complication that was not particularly fun.
As expected the 3 pairs each claimed one major hub. The first player went in the SE, to claim Atlanta-Richmond that was out early. 2nd went in the Northeast. The 3rd pair took the midwest and won from there, partially because one player was able to get into NY and complete NY-Chicago early, and go all the way to KC later.