Most everyone knows that if you waggle and knock a ball off a tee before actually swinging, it's no penalty.
But what if one of these things happens?
1. Waggle/address in fairway - touch ball before ever making a stroke, it oscillates but doesn't move. (Pretty sure no penalty)
2. Waggle/address in fairway - touch ball before ever making a stroke, it does move. (I think this is no different than causing a ball to move on a putting green at address)
3. Walking near your ball and accidentally bump and move ball with a club. oops
Rule 18-2 states - "touches it purposely (except with a club in the act of addressing the ball)"
But both scenarios 2 & 3 are accidental - not "purposely".
Still - I think BOTH 2 & 3 are penalties, regardless.
More interesting - if you read the USGA rule linked above - it says it's 1 stroke.
But then - at the bottom that section - it says -
*PENALTY FOR BREACH OF RULE:
Match play – Loss of hole; Stroke play – Two strokes.