I don't think I would ever use nearly that much. Certainly in a nut brown I don't think you'll need much sulfate. Even in something like an IIPA I don't think there's any benefit above ~300 ppm.
+1, that is unless you like getting Rhea...
FWIW, I think matching locale water profiles is not worthwhile, as a lot of breweries adjust their
water, not to mention the fact that profiles change over time.
Just use Palmer's sheet, get your RA in line with your SRM target, and your sulfate/chloride ratio right for malty/bitter and you should be fine.