Hi Tug,
I cannot understand how air pressure applied to the Number-1 cylinder will roll the engine to top dead center for that cylinder.
If anything, the piston would tend to be forced downward to the bottom of the stroke by the air pressure -- and even that assumes the piston was on the power stroke and both valves were closed.
We previously had a long thread about this topic. I will see if I can find that thread and insert a link here via an edit.
Regards,
Gadget