[camaraderie]

Copa...here's the documentation you asked for. Now shut the hell up about how it isn't bad for boaters.

BoatUS.com - Seaworthy Magazine

An excerpt:
"
The reports are all remarkably similar—a black sludge coats intake manifolds and builds up on intake valves, which soon destroys the engine. Most of the reports still involve fiberglass tanks made before the mid-80’s by notable manufacturers such as Hatteras, Bertram, and Chris Craft. We’ve even received reports from owners of small outboard powered boats that had been using portable fiberglass tanks.
Fiberglass/Ethanol Test Results
BoatU.S. sponsored lab test on two badly deteriorated fiberglass tanks to help confirm that the problems were indeed being caused by ethanol. The results, as expected, were not encouraging; though the report is full of hard to pronounce chemical names and expensive sounding equipment, the bottom line is that the tests indicate that two fuel tanks have undergone aggressive degradation—losing up to 40% of their strength. The report goes on to say that there is “resin softening and loss of adhesion between fiber and resin, evidenced by a moderate loss in both strength and stiffness.”

An independent test done by New Hampshire Materials Laboratory seems to indicate that ethanol reacts with chemicals in the resins and causes a reaction much like osmotic blistering, only at a much faster rate. The report says that ethanol dissolves uncured phthalates in the fiberglass (the same chemical that can cause osmotic blistering of a boat’s hull), which then pass through the engine’s filters and get deposited on the intake components.
Finally, chemical resistance data from a leading epoxy supplier showed that even epoxy can be attacked by ethanol. The test was made using the company's most resistant epoxy and exposing fiberglass lab samples to 10% ethanol gas and regular unleaded gas as well as diesel and aviation gas. The results for the ethanol gas showed a 10% loss in hardness and a 10-15% loss of compressive strength over a 16-week period and it’s likely that the loss of hardness and strength would continue to fall at a similar rate. The unleaded gas, diesel, and aviation gasoline tests, none of which contained ethanol, showed virtually no loss of strength.