Let's revisit what a normal cooperative (or competitive double is). It's a call where a) we believe our side has the strength to compete; b) there is no other possible action because we have insufficient cards in our suits; c) we expect (60%?) that partner will normally take it out but won't be surprised if he passes for penalties.
So, what's a cooperative penalty double? It's very similar. We believe that, based on the hand partner has shown so far, that the opponents will be going down in their contract. It's therefore a penalty double. Partner will leave it in probably 75% of the time, but we won't be surprised if partner takes it out.
Why would partner take out such a penalty double? For the simple reason that he thinks that he'll score more playing our own contract than defending.
A well-known case of a cooperative penalty double is made when the opponents sacrifice over our game bid (or our commitment to game) and partner makes a forcing pass. If we have no extra distribution, we will be, perhaps reluctantly, forced to double. But we will be thrilled if partner now pulls our double because this is the "pass-and-pull" maneuver which says that he's interested in slam.
Less spectacular was this hand:
Next up, from the same session, a much more controversial instance:
In other words, he is making a cooperative penalty double.
When I posed this situation to the BridgeWinners site, there were three votes for taking out into hearts, 18 for pass and seven abstentions. At least one abstention was because they would have bid 2♥ at their previous turn so the problem would not have arisen.
Here's the full deal:
I think one clear error was made, and two misjudgments, each worth half an error. In total these were the cause of missing the two tricks we needed in defense of 2♠X. West never showed that he had three hearts. Presumably, he intended to support hearts after he had created a game force with 2♦—so what happened? And both East and West had six card suits when they might only have had a five card suit.
Switch a couple of small red cards from the West hand with a couple of small black cards from the South hand and we get the following layout:
So, this example of the cooperative penalty double was not such a success. But I think it could have been, given a full understanding of the idea. I should note that in neither situation had this concept ever been discussed, or even contemplated. But in at least one case it did work well.
I believe that this sort of double can only occur after responder has made a forcing bid (such as a game-forcing 2/1 or forcing-1NT-with-invitational hand). One is that it is only when we have an expectation of being able to make game (or are close) that we would even think of making a penalty double that might be pulled for tactical reasons. [I don't count those situations where partner pulls with a weak distributional hand because that is a unilateral action, not one anticipated by doubler].
The other reason is a more practical one. There aren't any other situations where responder makes a delayed support bid. In the auction on board 5, West was only able to avoid immediately supporting hearts because he had a forcing bid at his disposal. After such a response, opener doesn't yet know if his side has a fit or not so he may easily try for a penalty only to have his partner show support and revert to plan A—bidding and making game.