Are they strong because they oversee and surveil important squares or reinforce defensive ramparts
which crops up much more often than in single rook endings
The Nimzo from both sides Strategy
Giving back material to gain a positional advantage
and an article by the originator "Botvinnik's debut practice
CLEARANCE - Tarrasch French I - Guimard Variation 3...Nc6 Chess King Chess Software Are they strong because theyThe Guimard Variation of the Tarrasch French (1 e4 e6 2 d4 d5 3 Nd2 Nc6!?) provides Black with an opportunity to avoid many of the stale and uninteresting lines of the 3 c5 variations, and also sidesteps the lines most under scrutiny by theoreticians. Since Guimard's advocacy in the pre war years, a number of notable players have adopted the line, including Belyavsky, Botvinnik, Hubner, Hug, Korchnoi, Larson, Ljubojevic, Petrosian, Short, Vaganian,