Metered debt payments accrue interest each month which must be paid before reducing the balance--for example, a $100,000 loan with $1000 payments that accrues $990 interest will pay down $10 for $1000. Deferred student loans accrue interest without pay-off, greatly increasing the cost to the holder.
Deferred student loans should be a market force not backed by the government. They are financially crippling and predatory. Each payment deferred costs twice as much, added onto the total cost; not to mention the cost of the loan in the first place, well exceeding the money borrowed.
Make the banks take the risk, rather than the taxpayers. Stop ruining the economy and stop ruining students' lives by saddling them with endless debt they can't understand.