I have been having trouble going flat and straight on my board. i am
unable to be stable when i point the board straight ahead and go
totally flat. i always have to keep a slight heal or toe edge. if i
do go flat it seems that my back wants to come around and then i catch
an edge and take a tumble. is this normal? do most of you also have
to keep a slight edge when bombing a run? I ride a Palmer Honeycomb
165. Thanks for any help.

Keep your weight forward and use the fall line...Once you have a good feel
for the edges, you will become more confident screaming down the hill flat
on your board not to mention edges are your worst enemy on the flats... It
helps to practice on nice smooth groomers...