D.C.
Rule #23 reads: "Players must remain at the table if they have a live hand." I will grant you this can probably be interpreted in different ways, but, in my opinion given the words used, specifically the term "live hand", I can make the argument that if the player is not at the table, then the hand is NOT live. A hand that is NOT live, is dead, is it not? In most cases, I believe that I would not make a ruling until the action came back to that player. If he/she was not at the table, for instance when the hands are tabled and read, I believe I would rule that hand dead, otherwise what is the purpose of the rule?
That said, looking at the later post by DaveChimp
This has nothing to do with folding an all-in bet. The rule that applies there is rule #9 which requires (emphasis added) to turn all remaining hands face up once all betting action is completed in an all-in situation. Since rule #9 requires the hand to be turned face up (tabled), rule #8 says "Cards Speak" AND rule #10 says, "Dealers cannot kill a winning hand that was tabled and was obviously the winning hand...". It would not be within the rules for a player to fold once all-in.
This is a similar to the situation you have when action is folded around to the SB and the BB is not at the table or the seat is being held for an absent player. The BB cannot win the hand and the pot is awarded to the SB.
I would be really interested in reading a response from MikeB, Pokerfish or one of the other TDA folks.
Hope this helps!