I've been reading the same book recently and here's another question that puzzled me:
If you had an engine failure between V1 and Vr and you had maximum crosswind, which engine would it be best to lose - upwind or downwind?
It give the answer is the upwind side - because the crosswind will oppose the yawing moment of the downwind engine.
However, surely the weathercocking effect of the crosswind on the fin will be yawing the aircraft into wind. The net yawing moment in this direction would be increased with an upwind engine failure. Conversely the weathercocking would oppose the yawing moment of a downwind engine failure.