I think it has to be recognized that the Celts, in some respects, barely won the Title. Atlanta, Cleveland both took us to 7 games, and Detroit and LA both took us to 6. Winning another Title with/or without Posey is hardly a done deal
Given his age, I think there is a fair chance that Posey's game starts falling off. He is not an allstar, who's game can fall off and still be better than most players.
Secondly, I don't think its a big stretch to see two step up from (TA, Powe, Baby, POB, Giddens) sufficiently to replace the impact that Posey had. And their games won't fall off, but will get better the year after that.
I think Ainge believes you can replace a role player, with another role player. The key to a Title is the 3 allstars, and perhaps Rhondo. As those four are getting more and more familiar with each other, our chances of a second Title are better. And Doc weaves in and out, whomever steps up from the remaining roster of role players.
Signing an aging role player to 4 years, going past the contract marks of Allen and Pierce is likely a mistake. Seeing others step up to replace his impact will likely happen. Given our greater flexibility, and the ability to replace the loss, our chances of winning another Title once in the next two years, are improved.
Either way, its a gamble. But I would venture to say that Ainge likely
has the odds down pat.
Frankly, our biggest role player weakness was not filled by Posey. If POB develops, this team improves significantly.