If he's already Rad then yes.
"I'm a moron for thinking the Browns could even sniff 10 wins in a division where the other three teams (two of whom almost always make the playoffs) made the post-season last year. Gyp Rosetti's thee God of football knowledge." - Brown Notes
Tough but not improbable. However your not going to get fair value, because the only way a team will take on Al for a rental, due to him being a FA. at years end is if you take on a bad contract the other team wants to get out of. I'd almost rather have him expire then take on a bad contract.
If Utah is securely in the playoff picture or fighting for a spot still come trade deadline, Millsap and Jefferson will still be with the team. The only way they go into rebuilding mode and trade them for players or picks is if the Jazz are clear out of the hunt. It is the same situation that happened with Boozer.
mellow's right, there are some challenges but he's not untradable. i think the problem is that right now the asking price is a little too high. as the next 8 weeks pass, the hope is that the jazz will get more realistic about what two months' worth of al jefferson will get them, or one of the current bidders will up the ante. probably some combination of the two.
the thing is, only certain kinds of teams are going to want big al - a team with no post scoring that doesn't mind that he's only a two-month rental (but in this case they're not going to give up long term assets) or a team that wants to create flexibility this summer so a 15M expiring is nice (but in this case they'll want us to take salary back). it only goes two ways - we can get crap for him, or we can get value but compromise some of our future flexibility at the same time. so the guessing game for KOC/DL is this: will that cap space be more of a commodity in the next 8 weeks, or later this summer?
as to the question of whether or not the jazz can generate a trade exception by S&Ting him if he leaves - i double checked, but i'm pretty sure this loophole is still open to NBA teams. in other words, we could pull a boozer/bron if another team decides to sign him for, say, 12M.
check out the jazzbros.com blog for more on the jazz.