The school would have to support this tactic. But, in theory, you could keep switching majors.
Another factor is that for some schools you have to get the degree within a certain time frame. At my alma mater it was 8 years for the BS. But, once again, if you switch does the counter reset? Dunno… I’ll ask tomorrow when they are open. 
Ooh, links:
See the ref’s at the end.
When I was in a state land-grant university, ROTC was mandatory for all males under 35, except those qualifying for an exemption (such as physical disability, foreign citizenship, etc.). One student was a pacifist and refused to participate in ROTC, so he was denied any degrees until he reached the age of 35, by which time had had taken and passed virtually every course in the catalog. As he also had a photographic memory, he had a perfect GPA, and was awarded a mountain of degrees as soon as he was relieved of his ROTC obligation.
He owes several times in loans what he might make in a year. Also, the loan payments each year are about $8600, while 4 classes/year (to be considered half time) is only $2800 or less.
http://sportsillustrated.cnn.com/college-football/news/20130909/the-system-leach-excerpt/
The same rule applies to students who have tried to sue this particular school. Mike Leach actually had the connections that he almost got the state legislature to pass a bill authorizing a lawsuit. Texas Tech’s behavior was blatant and obvious fraud.
Now that I’ve had a chance to do the math, your basic assumptions are wildly flawed.
First, most undergraduate-level programs define half-time as six credits, which is usually two courses, not four.
Second, under an income-based payment plan, Fred would have to make an adjusted gross income of around $75,000 a year and have a family size of one in order to have the payments come out to $716.67 a month. (The Federal Student Aid program uses AGI, which is gross income less certain deductions for things like student loan debt, contributions to qualified retirement plans, contributions to health savings accounts, and business expenses; someone in Fred’s presumptive bracket would be likely to have these deductions.) My calculations also assume a debt load of $100,000 at 6.8% and $100,000 at 3.4%, which is approximately the lifetime limit for federal student loans. Depending on his loans’ disbursement dates, he may be eligible for pay as you earn, which would lower his payment further. And, finally, depending on his employer, he may be eligible for public service loan forgiveness.
But your question wasn’t about the specifics of income-based repayment. It was whether it were possible to indefinitely postpone payments by staying in school and carrying at least a half-time course load. It is. Do people do it? All the damn time. Is it a good idea? Probably not because of the accrued interest on unsubsidized loans. But people do dumb things out of ignorance or because they’re following bad advice. (Going to grad school to ride out a bad job market is standard advice, partly because it allows you to postpone loan payments.)
Four courses, 2 in the spring and 2 in the fall. I guess the summer counts, not sure how many courses there are needed to be considered “half time” : probably just 1 course.
State Universities charge about $700-$800 a course, community colleges charge half that, I’m not certain what online programs charge. In any case, $2800 is a lot cheaper than paying $8600…and the tuition payments are tax deductible.
On top of that, “Fred” could make slow progress towards another degree or two that would actually help him make more money in his field.
Sure, as he does all this, the loan balance is accumulating. But, that’s just it : due to how much Fred owes versus his average career income, he won’t be able to pay off the loans under IBR anyways. So a bigger loan balance is irrelevant. Moreover, the 25 year clock on IBR forgiveness, I think, counts as a total number of payments. (25 years times 12).
So, it occurrs to me that “Fred” could start his own company later in his career. Most years, he would “pay himself” a bare minimum salary to meet expenses, and he would make IBR payments during these years. During this time, the company is accruing wealth. On years that he decides to “cash out”, by selling company assets and realizing the gains, he decides to enroll in half time at the local community college to learn Basket Weaving I and II or whatever. Since those years count as deferment, he doesn’t have to pay 15% of his income towards his student loan payments.
Ooh, thought of another idea. “Fred” could reinvest all the profits from his business back into the business, buying reasonably secure assets that can be sold later. He could have his wife’s income covering most of the family expenses, and she would file taxes separately, so that her income would not count as part of the income considered for Fred’s student loan repayment.
Hence, the income “showing” would be low enough that Fred would pay $0 in payments. Then, say, after 5 or 10 years, when Fred sells out the business and collects a couple million, well, that year is when “Fred” decides he has a pressing need to improve his skill at the local community college…
Sorry, but if you don’t pay yourself a reasonable salary, the IRS is going to start poking around in your business.
I just skimmed that : I saw no examples of them going after corps paying their officers “too little” for their services.
The problem is income taxes : apparently, they get charged twice if you do that. I guess the only solution is to use the same tax avoidance strategies everyone else uses, somehow. Corporate taxes are rarely paid, or so I hear.
Did you miss this?