It's pretty clear that things aren't working out in OKC and that George will be bolting during the summer. However, what if the thought is to try to salvage him leaving by gaining some value now?
Something along the lines of Smart, Morris, Yabusele, Larkin (eligible to be moved in a couple of days), and Nader work under the cap.
As for OKC, they're able to get Smart, who having played for Oklahoma State, would likely welcome signing there long-term. They also get a good contract in Morris and a prospect in Yabusele. Not the best of deals for George, but beats the alternative in receiving nothing for him. Besides, how many teams have the ability to beat that offer, have the confidence George re-signs, and are in position to win now? Larkin and Nader are salary filler and would likely be waived.
As for us, why not? Smart is looking to get paid and I'm wondering how much he'll command vs how much we're actually willing to pay. I'm confident that the allure of playing for Stevens and alongside Irving, Horford, and Hayward, he apparently is friends with the latter, would be enough to have him strongly consider re-signing in Boston.