Also, a US gallon is considerably smaller than a UK gallon. 2lbs of sugar in a US gallon would give a potential yield of a little over 14% - that's a bit on the high side. 2lbs in a UK gallon would be a little less than 12%, which is more sensible for a sugar wash.
There's a saying over here: "A pint's a pound the world around". That's just not true. In the UK, a pint of water is a pound and a quarter. Hey - it even rhymes!
