more of a suggestion...so moved
as for the whole new recruits issue, yes, large numbers of them do deadbeat, but this is one of the advantages of having a premium membership in that you can restrict who joins your game and when.
personally, and Lack may disagree with me, I dont think banning new members from doubles games is the answer, many people join specifically to play with/against friends of theirs and to force them one direction or another is quite a stick in the eye.
My suggestion would be to find a doubles partner before you join a doubles game as it is hard to trust a team member you have never played with or against before.
Twill