The scenario where I could see the Celtics trading for Tyson Chandler involves Carmelo Anthony opting out, realizing that the Knicks are stuck going nowhere, and signing with someone else and the Knicks blowing stuff up and trading Chandler for bad contracts and draft picks in July 2014.
Let's say Wallace, the unguaranteed contract of Bogans, a player selected with the 2014 Nets pick (or a pick), and a future protected first for Chandler and you have a team of:
Bigs - Chandler, Olynyk, Sullinger, Faverani, Bass
SF - Green
Guards - Rondo, Bradley, Pressey, Lee
A player taken with the Celtics own 2014 pick
A wing signed with the MLE who can back up Green and guard big SGs.
A veteran point guard who won't complain about a DNP-Coach's decision
A couple of extra roster spots for undrafted rookies, Colton Iverson, D-League guys, or bringing back Crawford or Brooks
Despite a presumably aging and declining Chandler, the team has extra first round picks, a rookie likely to have been taken with a high lottery pick, and young talent with upside.
That strikes me as a middle team likely to make the playoffs, on an upward trajectory for future seasons, so unlikely to be stuck as a perennial first-round exit.