Liza, Im not sure if MLPs have had an interest rate induced down cycle yet. The popularity has seemed to have been coupled with a low interest enviornment that has gone on for over 15 years. If the rate on the 10-year were to rise to say a more historical 6% I could see half the companies having to cut distrbutions and the other half having very little growth. The fact that the companies don't or aren't allowed to build some cash reserves for when the sea's get rough is sort of scary.
The Mayans predicted calamity on 12/21....everyone figured that it would be an earthquake, pole shift, or Planet X....but no, its interest rates, yes, increased interest rates, the scourge of equity investors....duck and cover!