I, too, didn't think about the lack of defense on Ty Lawson until well after the fact, but in retrospect, that decision was absolutely ludicrous.
Let's compare it to the 1992 Duke-Kentucky game. You know, the one where Christian Laettner gets the ball on an inbounds play with 2.1 seconds left to beat Kentucky in the NCAA East Regional Finals. On that play, Kentucky coach Rick Pitino opted not to defend the inbounds pass.
Pitino knew the decision wasn't a great idea, but due to the circumstances presented to him, decided to allow Grant Hill to inbound the ball undefended. Perhaps he overthought the situation; perhaps it was just bad luck. But regardless, Pitino cited valid reasons for not defending the inbounds pass. Furthermore, Pitino did have a man on Laettner, that man just wasn't able to prevent Laettner from scoring.
The Seminoles, with 3.2 seconds left in the game (read: more time than was left in the Duke-Kentucky game) not only chose not to defend the inbounds pass, but also didn't guard the person most likely to receive the ball (read: it took no effort whatsoever to get the ball to Lawson; perhaps they were hoping that he would trip over his own feet).
I am quite sure that anyone who knows anything about college basketball knows that Lawson can run the entire length of the floor, while dribbling the ball, in less than 5 seconds.
So again...why did FSU play absolutely no defense on in the inbounds pass? The more I think about it, the more it baffles me. I have yet to find an explanation.
But hey, I'll take the outcome of the game.