On Thursday morning, I estimated that, as I saw it, there was a 99.8% chance that Andrew Luck would choose to ply his trade in the NFL next season. By Thursday afternoon, I was glad that I’d left that 0.2% possibility of him opting to remain in college for another season.

Word came down Thursday that Luck would put off his big payday and return to Stanford for another season. The initial reaction in the media and in the blogosphere was simply, “Why?”

Why would a player forgo the chance to be the No. 1 overall pick and pocket a HUGE signing bonus to return to college for another year?

I’ve written extensively about my belief that players need to reach forward and grab their dollars when available. However, I’m also keenly aware of the desire to hold onto the college experience, the camaraderie and relationships for as long as possible. With graduation set for the spring of 2012, Luck cited his educational goals as the primary reason for his return to school.

His decision has ripple effects in both the pro and college worlds. Obviously, his decision to return to school changes the top of the pecking order in the draft. Carolina, which is just beginning the search for a coach, will need to decide how much stock it puts in Jimmy Clausen following his introduction to the NFL. Is he their quarterback for the near-term or long-term? Does the team have greater needs elsewhere?

It obviously sweetens the pot for coach Jim Harbaugh to return to Stanford for another season. Remember, there are no state funds dedicated to his salary, so there could be extra zeroes on his offer to match anything proffered by an NFL team. Harbaugh and Luck would team to try and build on this top-4 performance of 2010.

(I would be remiss if I failed to note that Arkansas quarterback Ryan Mallett announced his intention to enter the NFL Draft on Thursday afternoon.)

The decision to return to Stanford carries risk for Luck, as he’ll leave millions of dollars on the table immediately based on the sheer economics of the new CBA talks. That doesn’t even take into account the possibilities of a dip in performance or an injury.

I have no doubt that Luck did his due diligence and talked to everyone about the decision he was facing, including those who returned to school, and weighed the pros and cons. Last year’s No. 1 overall pick, Sam Bradford, certainly demonstrated that one could stay in school, and even with a significant injury, retain his lofty draft status and cash in.

Matt Leinart, who also returned to school and was later draft 10th overall, still pocketed some $25 million or so in salary and bonuses despite his struggles.

It comes down to two things.

1. How do you separate the tens of millions? You often hear fans refer to players and owners with the question, “how much is enough?” Barring a catastrophe, you’re still looking at a career that will net Luck tens of millions of dollars. So, go live the college life for one more year and build on the fantastic 2010 season.

2. I have always reviewed these situations from the point of view of — Go and get your money. Colleges (particularly Stanford and its monstrous endowment) aren’t shutting down. Your window to complete your education is a lifetime. Your NFL lifespan is generally very short.

Perhaps Luck turned the argument upside-down, as his father suggested in his post-announcement comments, and realized that the NFL wasn’t going anywhere, either.