I don't think deals like this are anything new. As mentioned, we did the exact same thing with Mikki Moore last year.
If Ridnour and Warrick were free to sign anywhere, the league would probably allow it. However, if the league found that we'd contacted their agent beforehand to arrange something, then we'd be looking at some sort of sanctions. It's the risk teams take when they do stuff like that.
What happens if the league finds out that it's the Bucks that say to the agents, "we want to buy you out so that we can make this trade with Boston to lower our payroll and get some operating cash but it will only happen if they know you would be very, very, very interested in immediately signing with them upon being bought out by us. Would you be extremely interested in signing with Boston if we did this?"
Technically Boston has no contact with the agents but there is definitely some circumvention going on.
If this is what occurred with the Mikki Moore situation, then I'm disappointed because I just don't like this type of rules circumvention though I guess it happens with buyouts all the time in the NBA. I just don't think it's right, even if it does benefit the Celtics, which, BTW, I can't say the Mikke Moore situation did. Moore was pretty less for the C's.