The problem with this scheme is that there is only one airplane. This makes the proposition a crapshoot...surprise mx items may come up, or they may not.

If they don't, the math works. If a biggy pops up you lose out. I have seen this go down both ways.

For something like this to work you really need multiple airplanes so you can amortize the risk of unplanned mx across the fleet.

Of course if your underlying motive is to build twin time vice make money, it might be worth the risk.