Thank you all.
For a very interesting set of answers and questions.
It would appear that this thread has started ot take on a life of its own. hayho thats what forums are about.
Hi Jon
I took on board the comment about pushers applying a downward presure on the noise wheel and did like you, i did a simple force vector diagram and i can see the point; that the rear wheels would act as the fulcum point so any force behind that point would apply a turning moment at the nose end, thus forcing the nose down harder than if the nose was being pulled (ie tractor arrangement). In that model the nose wheel would act as a falcrum point and the turning moment whould apply less presure to the rear wheels relative to the nose, but the nose would not dig-in as its being pulled.
however now i'm