I have been reading in the wiki about the scything and guillotine stroke. I would like to use these techniques. From what I understand scything is a rotational stroke and guillotine is slicing at a slight angle. Would there be any difference in effectiveness in cutting and closeness of shave?

How much of an angle from perpendicular to the direction of shaving can the edge be, as well the angle of the spine from the skin?

Thanks for advice