Consistently getting cannoli shells off their molds easily
Sometimes the simplest solutions are the best. I've found that simply increasing the amount of oil on the molds makes the shells slip off cleanly every time.

There needs to be a visibly thick layer of oil on the parts of the mold that the sheet touches. I've taken to using pourable vegetable (canola) oil rather than spray. I have the molds in a pan, pour the oil over them, and then take care to roll each mold in the oil to coat it thoroughly before wrapping a sheet around it.

It's surprising to me that so much oil is required when the thing is about to be submerged in oil, but it does make a considerable difference, and doesn't seem to affect the texture of the shell.