Compare an contrast this with Barclay Perkins' water treatment for their other beers. Very, very different.
Here's what it says for the mentally-thrabbed:
"Export & Draught Boil nos. 4 & 5 backs for 1.5 hours and alow if possible to cool to required temperature. No Gypsum added.That reminds me. There's a post about Barclay Perkins' water treatment I've had lying around, unfinished, for months. I really should finish it. It contains full instructions for reconstructing their water profile for each of their beers.
Dark Liquor not boiled, raise to required temperature, no Gypsum added."