Player (A) and partner (B) both lie at opposite ends of the same bunker (say it is 10 yards long).

1) A plays out and smoothes the sand. B plays and lands in the area A has smoothed. Any penalties?
2) A plays but fails to get his ball out of the bunker and it now lies ca. 5 yards from B’s ball. B plays and fails to get out of the bunker and his ball returns to approximately the same spot from where he just hit it. A now smoothes the area from where he made his (A’s) previous shot. B plays again and lands in the area just smoothed by A. Any penalties?

Re 1) there is no penalty as A was allowed to smooth the sand after playing his stroke.
and 2) again A was allowed to smooth the bunker after playing his stroke in the bunker

Thought on this... It would be a weak argument to claim that A was deliberately smoothing areas in the bunker with the intent to assist his partner
However if B had said to A "you play on I'll smooth the area you just played" and proceeds to do so then plays his second bunker shot and it comes to rest in the area just smoothed, B would incur 2 strokes penalty if he continued to play. Rule 13-2 Exception 2 applies.
The exception statement refers to player or caddie and does not include partner.
Rule 31-8 indicates A does not get penalised for his partner's breach of Rule 13-2 in the variation given above.

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