### Comment:
I can't see how it can go boobs up. Unless, of course, the corporate debt does not blow up.

### REPLY:
It can go tits up if the credit cycle doesn't tighten within your window. A tightening would necessitate a re-evaluation of the underlying bonds' ratings which would probably cause a string of downgrades. Once you get downgraded from BBB to junk, institutions will dump them en masse. They're required to keep a certain amount of investment-grade and some are not allowed to hold junks. 
  
 That's what you're betting on. You're betting on the credit cycle.

### END.