If you have no idea what system a pair is playing, it's kind of hard to figure out to what contract(s) they might have got.
Questions (for future reference in making rulings on this kind of case; I don't expect answers on this one):
1. what alert regulations were in force?
2. what convention card regulations were in force?
3. If NS were required to have CCs, did they have them?
4. Did West say he would not have doubled 3
♠ if he'd had correct information about NS's auction?
Jillybean's ruling is okay, up to a point. First you decide which law has been infracted (in this case Law 21), then you see where that law takes you (Law 21C takes you to Law 40C, which allows the TD to adjust the score if she decides the NOS has been damaged).
Has the NOS been damaged? Well, if West would not have doubled, they may have been, since 3
♠X made 4.
So how do we adjust? Law 12C2 says the NOS gets "the most favorable result that was likely had the irregularity not occurred" and the OS gets "the most unfavorable result that was at all possible".
North has 5 points. How strong does he think South is? If 3
♠ is forcing, then North might well have bid 3NT. At that point, South might pass, or he might bid 4
♥. 3NT makes maybe 6 tricks. Down 3 is -150, down 4 is -200. Seems to me 3NT-4 is "at all possible", and their worst such score, so I would award that to NS.
If the double had not occurred, NS might well have bid on to 4
♠, and gone down 1. I suspect its' likely West might have doubled that, so 4
♠-1 for EW.
I've made assumptions here that I would prefer not to make when making rulings. I would much prefer to know what NSs system actually is. But you can't always get what you want.
This is a judgement ruling - I would inform both pairs of their right to appeal (Law 83).
I agree with reminding EW to alert when required - call it a procedural penalty in the form of a warning, and if they fail again, issue a PP in imps.
West's opinions about the playability of the board (they did, after all, play it!
) and what the ruling should be are (a) irrelevant and (
incorrect. 'Nuf said about that.