Davis can't be signed to a big enough deal to match Boozer's salary (BBD is limited to no more than the MLE in the first two years of any deal), and even if he could be, "base year compensation" rules prevent it.
I should have mentioned Davis's $4.75MM salary.
Since Portland is involved, they are absorbing the cap space difference to make this deal work. If they aren't involved, this doesn't work. Since they are, it does.
From Boston's Perspective
Outlaw: $4MM translates to $3.2MM with the 25% difference in salaries
$3.2 - $.0.825 (Pruitt's salary) = $2.375 MM in a cap hit
Since BYC rules say that Boston can only take 50% back, that $2.375MM can be multiplied by 2 ($4.75MM).
Won't happen, Pruitt's deal won't save them very much money if they're forced to have Glen Davis to a hefty contract. Utah needs to work out a trade with a team under the cap and a whatever team gets Boozer.
Utah would be saving $16MM in this deal when you consider the dollar for dollar luxury tax
The deal is involving a team who is under the cap. The only difference is the Celtics are trading Pruitt and Davis for Outlaw. Pruitt would be non tendered.