I spend my daylight hours hearing roadshow pitches from oil and gas prospectors who explore producing wells one property at a time. These wells are difficult enough for a small company with limited finances. Pooling single wells into MLPs aggregates their production and enables partners to allocate capital where it can add the most to production. Pipeline MLPs are intriguing for a related reason. Their cash flow is the result of amalgamated production in large regions, regardless of how poorly a single well may be performing at any time.
Applying some Boglehead theory to MLPs leads to the conclusion that MLPs arbitrage away risks specific to single wells and pipelines. It follows that an ETF of MLPs would arbitrage away risks of local geography and single MLP structures, leaving an investor with broad exposure to a flow of hard assets.
I will posit that the cash flow generated by an MLP ETF is a rough substitute for the cash flow generated by fixed income investments. One crucial difference can make all the difference in a hyperinflationary environment. Inflation gradually destroys the principal value of a fixed income security and reduces the real value of its coupon payments. Even TIPS may not be immune to this destruction if their principal resets are not frequent enough to keep pace with inflation, or if the resets are based on artificially suppressed CPI calculations. A hard asset ETF such as an MLP ETF may not suffer such a deficiency. Its cash flows are derived from the nominal value of payments made for resource flows, so its value should theoretically hold during hyperinflation if it is rapidly marked to market.
The only MLP ETF I am currently considering for this role in my portfolio is the Alerian MLP ETF (AMLP). I have not purchased it yet for several reasons. First, it trades at a multiple of 22 times earnings, pretty pricey given the economy's long term average P/E of 14. Second, its expense ratio is frighteningly high at 0.85%. Finally, it has only been around for two years, and has not paid enough coupons for me to find its value using something like my REIT ETF valuation methodology. I believe that methodology is applicable to an MLP ETF because REITs must pass through their cash flows as dividends to shareholders, just like MLPs.
I like that AMLP is optionable, so that if I did own it I could write short puts under it while inflation drives it up. Other MLP substitutes like ETNs don't have that flexibility. Come to think of it, I may decide to buy into it despite my reservations above if inflation really does get going. Bargain or not, hard assets that generate cash flows bring the best of many worlds when hyperinflation starts destroying the value of everything else.
Full disclosure: No position in AMLP at this time; this disposition could change with the onset of high inflation in the U.S.