Economics is a branch of social science that deals with the consumption, distribution, and production of goods (Webster), Adam Smith theorized the Wealth of Nations which theorized modern day economics.
There's a big difference between economics in which we use it, and the way baseball uses it. Hammer, I will make my points with more civility from now on.
Continuing, I guess you could say that in baseball, it would not make much of an economical sense for a baseball team to give Jason Giambi who will be 37 when is contract expires in three years. I can't find a precedence in which a ball player gets a big contract at such a late age.
As for leaping off the roof theory, if he did it the first time, what makes you believe he'd do it again. I can imagine after Giambi was diagonsed with a tumor, and was told by doctors, that this may be life threating, and you may put yourself at an even greater risk if you are to put any more steriods into your body. Just imagine hearing that, and you're single. But Giambi has a wife, and she hears that, do you think Giambi is going to want to put her through that? Sure, some ball players are arrogant, pompous *******s like Barry Bonds, but Giambi isn't that kind of guy. He wants everyone to like him, he was the clubhouse leader in Oakland, I seriously doubt he'd put the people he cares about in that kind of position again.
You can say all you want the Giambi is on steriods, and after he went on that HR binge, don't you think Bud Selig raised an eyebrow? That's probably why Giambi has been tested, at least once.