When I find an error it's only polite to correct it....we went back to the Hobgoblin in Sannomiya last weekend and discovered to my shock (at having told a porkie on this blog) and delight (at being able to now afford it), that the Sunday Roast is actually only 1400Yen (about 7 quid)!. The 4000Yen version is for a party booking and includes all you can drink for 2 hours (which in fact is quite a bargain). Apologies all round to the Hobgoblin Pub.
Haven't tried the roast yet, but will let you know.