Very true. I had a new GFCI installed for a new outlet for my brew system. It tripped instantly, and while I didn't think the system was at fault, but it seemed odd that a brand new GFCI would be bad. And yet, it was. Everything worked fine after that faulty GFCI was replaced.
I haven't done it, myself... and I don't know how you'd do the calculations -- you'd probably have to wing it and just keep checking the gravity, but...
At least one brewer I know has mashed and sparged with wort (instead of water) to create a big beer. I think it was a barley wine in this...
I'm seriously considering an RO system lately. I've been trying to learn more about adjusting my water, and it just seems like building the water from scratch is a lot easier, especially for a few specific styles.
Wouldja believe there was a Zymurgy article on brewing with cicadas 20 years ago?
"By May 22, Marler had accumulated enough cicadas to brew 12 gallons of barleywine, which he called CicadAle."