John

What rule do you believe he breached ?

Guessing you could call it grounding the club but I imagine that only applies to the club you are using to play the shot. Not sure

One for the rules gurus!

See 13-4/0.5 bullet point 2

Further, I would suggest that if the player is not holding the article(s) he cannot be testing anything.

John Foster (16) wrote (see)

What happened to the tour pro in America who was standing in a bunker to hit his ball which was outside the hazard and put it into a bunker further up, when his caddy raked that bunker he was awarded a 2 shot penalty.

Another situation than the one we're discussing here, but he was DQ'ed for handing in a wrong score.

He did not add the 2 penalty strokes for testing a bunker. 

But since that penalty the USGA issued the following.

click