Multitude of factors to consider:
1) Gordon Haywards injury impacts ability to truly compete this year (although I strongly disagree with this notion given the play of our rook)
2) Age
3) Center heavy draft next year with Lakers pick likely conveying.
To get back to the op here...
1) Irrelevant. GH is out this year, but both players have years after that. We weren't really contending this year anyway. We need AH for the two years left after this one, when we may very well be favorites in the east (in no small part because of Al).
2) Irrelevant. Age ain't nothin' but a number. His mobility is fine. Still plays the 4 as a big after all. No serious injury history to be of concern.
3) Irrelevant. We need more big depth, not less. Keeping Al plus drafting a big is just fine.
So, yeah. Not really a thoughtful idea. Would upset winning culture the youngin's are steeping themselves in, which could negatively impact the franchise in a major way. Not worth a moment's serious consideration.