I've usually mashed my Celebration type beers ~ 154F. And I don't doubt that SN mashes that high (but am surprised), so I have to assume that they use a ton of gypsum to achieve that balanced finish, like maybe ~ the 300ppm level of sulfate in Bru'nWater's Pale Ale profile. I've only used the higher levels in the last couple of years and the results are undeniable in a West Coast-type beer.