Not sure what I want more....
...Smart not signing and so plays out of mind trying to increase his value for his unrestricted free agency.
...Smart signing and being happy, plays like he feels he has to show he was worth the contract.
Now, that not signing scenario could go bad because feeling he needs to show his value, he shoots too much, not getting any better at it and hurting the team. The signing scenario could go wrong, as well, as getting the big contract could cause Smart to coast knowing he is now making bank.
Thing is, knowing what we know about Marcus, him trying to be great too much is way more in his nature and likely than him coasting. So, if he signs, maybe knowing he has his money, he will start to play more within himself for the betterment of the team, as he doesn't have to put pressure on himself in trying to have a season that lands him the big payoff in unrestricted free agency.