Kevin Pacey wrote on Tue, May 23, 2023 02:25 PM UTC:
One theoretical curiosity is that there is the old rule of thumb (from gambit openings!?) that in open positions, a tempo is worth 1/3 of a pawn. If we accept that the bishop pair is worth half a pawn then it would seem that gaining it is usually(?) worth more than investing a tempo in an open position.
In closed positions, presumably with time not being as vital (usually), a tempo would be worth less than a third of a pawn. Yet, the Nimzo-Indian (1.d2-d4 Ng8-f6 2.c2-c4 e7-e6 3.Nb1-c3 Bf8-b4) is a highly respected black defence in closed games, with black often happily allowing white to gain the B-pair for (virtually) a tempo (or sometimes not even for that), namely via a2-a3 by White (not too useful a move usually, except for inducing the trade). Any other factors involved in assessing the huge variety of positions arising from this opening are less permanent or constant, perhaps, maybe with the exception that there is the initial fight for the centre being engaged in by black. If assessing values is that sensitive, I still wonder how reliable computer studies are, with the initial positions of the setups chosen maybe not being always nearly complete enough.
One theoretical curiosity is that there is the old rule of thumb (from gambit openings!?) that in open positions, a tempo is worth 1/3 of a pawn. If we accept that the bishop pair is worth half a pawn then it would seem that gaining it is usually(?) worth more than investing a tempo in an open position.
In closed positions, presumably with time not being as vital (usually), a tempo would be worth less than a third of a pawn. Yet, the Nimzo-Indian (1.d2-d4 Ng8-f6 2.c2-c4 e7-e6 3.Nb1-c3 Bf8-b4) is a highly respected black defence in closed games, with black often happily allowing white to gain the B-pair for (virtually) a tempo (or sometimes not even for that), namely via a2-a3 by White (not too useful a move usually, except for inducing the trade). Any other factors involved in assessing the huge variety of positions arising from this opening are less permanent or constant, perhaps, maybe with the exception that there is the initial fight for the centre being engaged in by black. If assessing values is that sensitive, I still wonder how reliable computer studies are, with the initial positions of the setups chosen maybe not being always nearly complete enough.