Let me correct Bill Gross a bit here

Here’s Gross:

• “Pretend...the bank owes you a buck any time you want to withdraw it. But the bank says to itself, “she probably won’t need this buck for a while, so I’ll lend it to Joe who wants to start a pizza store.” Joe borrows the buck and pays for flour, pepperoni and a pizza oven from Sally’s Pizza Supplies, who then deposits it back in the same bank in their checking account. Your one and only buck has now turned into two. You have a bank account with one buck and Sally’s Pizza has a checking account with one buck. Both parties have confidence that their buck is actually theirs, even though there’s really only one buck in the bank’s vault. The bank itself has doubled its assets and liabilities. Its assets are the one buck in its vault and the loan to Joe; its liabilities are the buck it owes to you – the original depositor – and the buck it owes to Sally’s Pizza. The cycle goes on of course, lending and relending the simple solitary dollar bill (with regulatory reserve requirements) until like a magician with a wand and a black hat, the fractional reserve system pulls five or six rabbits out of a single top hat.

He has two errors, one the central banking error and one his own.  The central banking error is betting time, not probability.  The depositor believes, rightly so, hy he can withdraw a demand deposit. If time is not guaranteed, then the central bank should cause an asynchronous interest payment swap to bring all balances back to the proper congestion level.

The second error is that he assumes the tiny bit error is static.  It is not, iy will grow and shrink as currency risk grows and shrinks, also a esult of asynchronous amortization payments.  

So, the correct answer is,yes,there is risk, but the risk is bound by the precision of the S&L buffer, which is a parameter.  Central banks crash because they promise transfer payments way beyond their mark to market due date, so Congress inevitably has to suddenly call some commission and update the ins andouts of transfer payments. The central bank then suffers duration losses as everyone changes retirement plans. But this is normal, just not  every 40 years, try every 5 years.