Really? A half kilo of black and another half kilo of roast doesnt suggest too much to you stu? Looks a bit epic to me, but then im not that good with my dark beers, im allways too scared to be heavy handed with the dark malts...
Not at all - it's under 10% of the grain bill.
You wanna try Kieran's imperial Stout - I think he uses about 5kg roast for 50L. At this rate Soren would be using 2kg!
and there's 13% roast (apparently) in Townshends 4% stout!