Here's a hand from a while ago. I held:
Partner North starts the auction (we're at unfavorable):
1♦ - pass - 1♠ - pass
2♣ - pass - 2♥! - Dbl
pass - pass - ???
(!) 4th suit GF
Now what? Partner doesn't have anything useful to mention over our 4th suit forcing (the Double gives us more possibilities), so partner will either have Ax or xx, perhaps even xxx imo. So I decided to pass, since it was unlikely we could get a game score ourselves, but we can probably manage 8 tricks in a 4-2 fit on hcp-power.
The full hand was:
According to GIB a small ♥ lead defeats the contract by 1 trick, all other leads let the contract make. Opponents made a mistake in their defense and I made 2♥D+1 for +570.
As the cards lay, 3NT is laydown, but I didn't expect ♥K in partner's hand. The Ace was possible, because partner may want to rightside the contract when I have Qxx.
Doubling on such low level is dangerous, especially if you don't see an immediate way to defeat the contract. With the West hand, you can hardly see 6 tricks coming in (♦K wrongsided, too many ♠s, and no great trump holding), so it's probably safer to pass and trust on partner's lead skills to defeat the contract. You might even get another chance at 3-level.