Pipeline MLPs have been crashing (down 50% over the last 16-17months) along with the oil producers as a sympathy trade and general risk aversion to anything energy related.So the market is valuing the pipeline businesses similarly to the rest of the energy sector. SO they are not completely immune from the energy sector trade-down.
Additionally, MLPs have IDRs (incentive distribution rights) thus, they are incentivized to increase distributions, as the percentage of the distribution that the GP gets grows as the distribution grows up to a certain tier.
IIRC a number of the larger pipeline MLPs have reduced their distributions (dividends). KMI comes to mind immediately, and ETP is likely soon to follow.
The pipeline MLPs distribution coverage ratio have been falling over the past 90 days. Some of this is self-inflicted.
The supply and demand economics of pipelines is regionally focused. Like I said before it has alot more to with the give and take of transporting crude across the US to buyers that have specific crude requirements and sellers that have capacity of certain crudes in certain geographies. The macroeconomic effects of crude price don't have dramatic effects on this.
The lifting of the crude exportation restrictions is a very recent development with very little effect on the marketplace in the short to medium term. It will really only benefit the market as the infrastructure for facilitating physical exportation is developed.
Lastly, while we haven't, in the past, been exporting crude, we (the US) do export LOTS refined product to the global marketplace. Developing nations without the refining infrastructure that the US has are willing to pay much higher prices for refined product net of transport cost. So the pipeline boys haven't seen the slump nearly as quickly as those on the E&P (exploration and production) side.
At the end of the day, the entire energy sector is being valued as a "bad asset" by the market, there is certainly SOME mispricing going on.
The pipeline guys don't feel the crude macro like the E&P folks to because they are insulated from it because crude transport must still occur.
What is definitely falling off if the marginal railcar load. Over the past few years rail has been used where pipeline geography and/or capacity were impediments to efficient transport. Crude transport over rail got creamed in 2015.
I'm not surprised that distributions haven't "fallen off a cliff". The pipeline business is relatively steady and boring. I personally do not believe the sell-off in pipeline MLPs is merited, therefore any of the positions I initiated in 2012 I have not touched, which is rough on relative performance. If I wasn't already fully allocated in energy I'd be buying pipeline MLPs with great dist cov ratios. But I already have them :)
But getting back to the original post, this has less to do with "how efficient" the market is in the energy sector. The information is disseminated in a timely manner.
The thing you have to remember about "market efficiency" is that it's a great theory/hypothesis but nature doesn't always cooperate. "The market can remain irrational longer than you can remain solvent"
One of the most important underpinnings of classical economics was the assumption of "a rational participant". Research in behavioral finance (e.g. Thaler et al) over the years has shown that humans are remarkable in their ability to behave irrationally, or in a biased way.
Thinking Fast and Slow by Dan Kanneman (check last name spelling) is a great read on cognitive bias.
If the market was perfectly efficient there would be zero opportunity to exploit mispricing, because no asset would be mispriced. But history shows us that's not true, so we have to take at most a semi-strong market efficiency view for it jive with past events.
Your original assumption that oil demand is up seems off to me. Overall, compared yoy oil demand is down, which combined with no slack in crude production is the reason why oil prices are trading at 2003 prices. It's brutal if you look at the 20 year chart.
ETA: this post wandered a little, but it's late and I think you can tease out the points. Good discussion though.