Originally Posted by ContinentalFan
Here's a question, with the alliances--such as SkyTeam, the one with which I am most familiar--it is possible to circumvent minimum stay rules and accrue the necessary mileage and EQM or points. It's easy to nest tickets such that you don't have to satisfy a Saturday night stay. I am sure they could try to end this activity too; however, I don't know when anti-trust issues kick in. Taking advantage of codeshares of alliances might be harder for airlines to police.
I'm not sure I completely understand the specific scenario: it sounds like you are talking about buying 2 tickets - say, one from CO and one from NW - where one of the two is nested inside the other to avoid Saturday night stay rules. Then, you credit the EQM's to the same FF account since they are in the same alliance.
IANAL and I don't know how the contracts of carriage are worded with respect to codeshares and alliances. It sounds illegal for airlines to share passenger data in this way, but who knows...
Although I think basic nesting rules on 1 airline are bogus to begin with (again, they possess the data about what you intend to do at the time you are pricing the 2nd ticket, yet they sell the ticket), but that's neither here nor there. I still wouldn't want to deal with the hassle of getting caught. On the rare cases where I need to nest 2 tickets, I just take the middle trip on a different airline.