my thing is why would ATL do it?
I agree, the only way I see this happening is if Smith is really causing management headaches and they just want him gone. If that is the case I don't understand why they wouldn't try to trade him for a real center to try to move Horford to his natural 4 position.
If some how the celtics did end up with Smith, using the trade I proposed above the next key would be trading Bass and Dooling for a SG or C.
Maybe try S Young (from my previous trade), Bass and Dooling to phoenix for C Frye and S Brown? Frye is a 4 year deal but for pretty reasonable.
Then the Cs resign KG,Pietrus,S Brown, Wilcox, J Green in the offseason. We end up with a "young veteran team" mostly 26-30 year old, two hall of famers, and two young guys. Rebounding will still be an issue but if KG can hold up we actually match up pretty nicely with miami.
2013 Celtics
C KG, Frye
PF Smith, Wilcox, JJJ
SF Pierce, Green
SG Pietrus, S Brown
PG Rondo, Avery