If Ainge does re-sign Rondo somehow it will not be because he has any unwavering belief in Rondo's ability and place as a top PG. It will be because Ainge hates losing assets. Ainge was more than willing to deal Pierce but only when a deal like the Chris Paul one came along. Eventually the Allen/Garnett thing happened and keeping Pierce became the best choice.
Ainge was more than willing to trade Pierce, which doesn't mean he didn't believe PP was a top sf.
What I meant was he's not afraid to deal stars but only if the right deal comes along. He's never dumped a player with value just to dump them and lose as many games as possible.
D.O.S., I don't think the extra year the Celtics can offer is much leverage. Not when Melo and NYC endorsement money is waiting in the offseason. Look how Marbury used NYC and the Knicks brand to pump up his apparel line. Not that Rondo has the same entrepreneurial spirit but the New York hype machine is ready to blow Rondo up just like Francis, Stoudemire, Marbury, and others before him.
I think that, faced with the decision Rondo will take one year less since the Knicks don't have much to trade. Or, Ainge will negotiate with Rondo to make a deal before the trade deadline for an expiring like Stoudemire/Bargnani, Shumpert, and a 2018 pick. That only happens if Rondo convinces the Knicks that he really wants the fifth year though.
Rondo is controlling the situation, not Danny or any of the owners. The extra fifth year is just not a big enough deal for certain players and situations.