As the title says 'What direction of grinder rotation'.
It might sound like a strange question but does the direction the wheel rotates, with respect to the tool, make any difference?
To explain;
My Dry Grinder rotates onto the tip of my tool, abrading from the tip to the heel of the bevel angle.
My Wet wheel however I use from the other side, such that it abrades from the heel to the tip of the bevel angle.