[Retros] More switchback mates

[Nicolas.Dupont at math.univ-lille1.fr]

> Here is the latest idea (Reytsen▓s, not mine!) with a rook:

> 1.Pb2-b3   Pe7-e6   2.Bc1-b2   Ke8-e7   3.Bb2-f6   Ke7-d6

> 4.Sb1-c3   Kd6-c5   5.Pb3-b4   Kc5xb4   6.Ra1-b1   Kb4-a3

> 7.Rb1xb7   Qd8-e8   8.Sc3-b5   Ka3xa2   9.Rb7xc7   Bf8-a3

> 10.Rc7xd7   Ba3-c1   11.Rd7xa7   Ka2-b1   12.Ra7xa8   Bc8-b7

> 13.Ra8-a1


One can achieve the same goal faster :

1.Pe2-e4   Pg7-g5   2.Re1-e2   Ff8-g7   3.Re2-f3   Fg7-d4
4.Rf3-g4   Cg8-f6   5.Rg4xg5   Th8-g8   6.Rg5-h6   Tg8xg2
7.Pe4-e5   Cf6-g4   8.Rh6xh7   Tg2xh2   9.Rh7-g8   Th2xh1
10.Pe5-e6   Th1-h8

Best,

Nicolas.