I don't understand what he's wanting to do that's not already done. The direct loan federal student loan program ALREADY offers income based payments that is based, I believe on an exact 10%. You pay the monthly payment until 50 years. If there is a balance owed after 50 years, it is dissolved.
I am a student myself and while unfortunately, I was forced to carry student loan debt, my repayment method of extended graduate was cheaper than income based, as will be for almost all graduates unless they are simply not employed. In addition, you have a 6-month grace period after graduation and if you are not employed, you can file for an additional extension.
Maybe Obama needs to do a little research.
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