Sorry for taking a few days to get back and respond.
I originally asked just to get a feel for how rare this situation is. I am currently in a unit where our CO has two troops and one pack. I know that we are unique in our council, but wasn't sure how many other situations like this there are nationally. Whenever I have explained that our CO has two troops the most common response is, "I didn't even know that was allowed".
Our CO chartered its first troop in 1941. The pack was started in 1951. Sometime in the 1970's a series of events led to them chartering a second troop. The story I have heard is that the first troop was very large, the council wanted a second troop in the area, and the CO said "We love Scouting, let us have another one", so they did.
Both troops are relatively healthy. One has about 40 scouts, the other about 30. They have very different personalities, but tend to stay out of each other's way. The only real conflict comes from both units trying to recruit from the same pack.