My speculation..granted I am not very good at it.
My picks for new teams....and why I think they are there:
Yasur: Ami, Eliza, Leann, Julie, Lisa, Rory, Travis
Lopevi: Lea, Twila, Scout, Chad, John, Chris
If Lea is told to swap 2 member from each tribe(which is what i believe happens) he will pick Twila and Scout because they are older and work harder. He puts Rory andTravis in Yasur because he doesn't like Rory and believes Travis to be a liability in water challenges. Therefore my assumption on the betterteam to win Rc is Lopevi..they have far more stronger swimmers that Yasur. Hope this helps a bit.