Enter Your Reply The Comment You're Replying To Roberto Lavieri wrote on Sun, Mar 21, 2004 07:14 PM EST:Advantage in the exchange is REALLY difficult to measure, it depends strongly on position, and FIDE-CHESS is a notorious example. G.M. Tigran Petrossian, ex-world champion, was famous by a strict positional Quality sacrifice in some openings, giving its Rook for a Knight without any apparent advantage. After a lot of moves, say 20 or 25, the advantage was notorious, but not easy to see at first!. Edit Form You may not post a new comment, because ItemID Game Design does not match any item.