I think it's an excellent bid. I had:
I bid 3♦, which is the only option really. This was passed out. There's five top losers and it went one off. This was a good result though, as the opponents are easily making 3♣, from their seven Clubs tricks, ♠AK and the ♥A for an overtrick. Anna's boldness gained us 2.3 IMPs, off to a good start!
Then, at favourable vulnerability, we dealt out some massive punishment to the opponents. What does South's double here show?
It's presumably some sort of takeout double, showing Spades. But not sure what partners supposed to do if they don't have Spades. Also, North-South were vulnerable, and the opponents had unlimited hands with no known fit. It was a mad double, but I think most of the time you would get away with it. Not today though.
After South's double I redoubled, showing a good hand with interest in penalties. No one understood my bid, and North clearly didn't know what was going on and bid 2♥. Anna was confused and passed. South wasn't done and bid 2♠, which I doubled. Anna was happy to pass this, and declarer was in massive trouble.
There's lots of silly results on BBO, this time the silly result was from our table. We only need to take 2♠x off two at this vulnerability for a good score, but actually declarer only got one high Heart and a Club ruff in hand, for 2♠x-6 and -1700.
Those were two good Boards, now for a very bad one. Anna has been reading Sabine Auken's book I Love This Game, and there's a bit in it about Lightner Doubles. Although we'd never discussed it (and definitely don't play them), I thought I had the perfect hand here so pulled out my first Lightner Double. Needless to say, Anna was not impressed, and my adventure backfired badly. Here was the opposing auction, and my hand:
Don't worry, I found the killer double. Since it's so rarely profitable to double 3NT for penalties, a double instead asks for an unusual lead, specifically dummy's first suit, which here is Hearts. It's a Lightner double! I thought declarer would be ready for a Spade lead, but probably have nothing in Hearts, so thought I wanted a Heart lead.
However, South escaped to 4♣. I hadn't considered that the opponents had a big Club fit, and so an easy escape. I felt a bit cheated here, and was tempted to make a follow up double of 4♣, but rightly I think passed. South was left to play in 4♣. Now I had to hope that 3NT was making, and my double had forced them out of their making game. In fact the opposite was true, 3NT was going at least three off and I'd forced them into the best partscore. This was the sorrowful full deal and auction:
You can see that North-South have both overstretched to bid 3NT, on a combined 18 count. What of my Lightner double? Well, a Heart lead is indeed effective, but then so is the obvious Spade.
Afterwards, I wondered how East-West were supposed to reach their easy Spade game. Unfortunately, Jake was kibitzing and made a private comment to Anna, suggesting perhaps I could have overcalled 1♠. Maybe next time.