John Lawson wrote on Thu, May 29, 2003 06:09 PM UTC:
'Now, promoting a Rook to Queen, dispite the gain of 1.5 to 2 Pawns is
less obviously a good idea because of the leveling effect.'
And because it takes two tempi, not one. You can use two tempi and two
Pawns to change a Rook to a Queen, two Bishops and two Pawns to two Rooks,
or a Rook and two Pawns to three Knights. Or two Bishops and two Pawns
into four Knights. Which would you rather have? That is a question
anawerable only by playtesting.