I'm a new grad student preparing to do some work on Daya Bay, and I'm basically taking in all the information on neutrinos that I can right now. It's pretty interesting stuff, but I was wondering if anyone has any thoughts on the following: Assuming I correctly understand that neutrino flavor is defined solely by the type of charged lepton involved in a CC intereaction also involving the neutrino, and also assuming that I correctly understand that a neutrino flavor is a superposition of three (maybe) mass eigenstates, then I believe it is safe to say that the mass of the neutrino involved in a CC interaction has nothing to do with the associated charged lepton. So I have to wonder, what property exactly is it that a neutrino possesses that influences the outcome of a CC interaction? Don't say flavor. I've looked around, and haven't been able to find a single instance where anyone has asked this question, much less attempted to speculate. Thanks.