A player who assumes his stance, formally addresses the ball, and then fairly strikes at it, but in so doing fails completely to make contact with any part of the ball, is deemed to have performed a full-address rehearsal of his swing (practice swing) and therefore need not count a stroke provided that he strictly observes the following procedure:

1. He must immediately readdress the ball with the same club, and his next stroke shall be counted regardless of result.
2. He must not exhibit any surprise or dismay or suggest by gesture or facial expression that he ever harbored an expectation or belief that his swing would cause his ball to undertake any forward movement whatsoever.
3. He must make no remark disparaging the course, the prevailing weather conditions, the state of his  equipment, or the level of his own playing skill, other than a statement speaking not of the fortuitous elimination through practice of a faulty swing or a declaration of an intention to strike at the ball with less force or in a more controlled and measured manner when making his actual, true, real, final, intended, and accountable stroke.

The attorneys with Roach, Geiger & Caudill neither endorse nor condone the use of the above in a competitive environment …unless, of course, a distinct advantage can be derived therefrom.

Source:  The Official Exceptions to the Rules of Golf, Special Titanium Edition, by Henry Beard, copyright 1992, 1997 by Henry Beard and John Boswell Associates;  Villard Books, a division of Random House, Inc., www.randomhouse.com