Regarding the journey, I did look at adjoining fields when on a train visiting relatives outside London.
Some fields were easy to get to. Others looked much harder. With hedges, trees, fences, dips and mini streams seperating fields. Often a combination of these.
So not much chance of Bamber being able to walk from GH to WHF in a straight line.
Wilkinson also said it was not possible.
Zig zagging across the difficult terrain of fields would be too tiring and time consuming.