I'll have a try at this. Forgive me if I get this wrong, though, as the whole game is very new to America. We tend to like our contests to be bloody and to end on the same day they start. And I haven't studied quite as many strategy guides as you lot, but I have been trying to keep up with the best-selling American book on the subject: Heathrow to Westminster for Dummies. Based on that:
Reposition to the Harrow Stations - Ruslip to Preston Road, double back North Harrow. That's all three.
Sorry if that was too simplistic.