Congratulations, I hope to do the same someday; although I hope all my kids are whole.
To date, I've been lucky enough to develop the right personal and profesional skills and graduate during a time when jobs are plentiful. Although I agree that I haven't "distinguished [myself] to the point of extraordinary reward", this does put me in a position to choose where I work based on a number of factors. I certainly don't expect to make a deal that no one has ever been offered before, but if it is not uncommon for that company, I would want to discuss the possibility with them.
As an employer, I would be willing to make exceptions for those employees who were worth it.
For reference, one HR department said they pay for any classes that you can prove benifit a healthy work/life balence. IE. art class, physical fitness class, and of course anything relatinng to your job description. This company obviously understands that happier employees are better employees. This also reduces turnover as well as costs associated with recruitment and training.
If agreeing to pay of an employees student loans, even if this results in a lower salery, helps him achieve piece of mind and in return become a better and more committed worker, then I feel it could be worth it for the company.