- row shouldn't be underestimated. At each turn white plays two moves with
- only one constraint: do not be under check in the end.
- So if the white king attacks a defended piece, he can take it anyway by
- coming back on its initial square on (sub)move 2.
+ row shouldn't be underestimated. At each turn white plays two moves
+ without any constraint. The goal is to capture the king.