What do E/W do when it goes 1
♠ - 4
♣ (alert)? If they routinely ask then they do not give UI in this situation, and so South's infraction is the only cause of information being transmitted. It would be inequitable to regard it as unauthorised for E/W.
If they do not routinely ask then they are probably transmitting a lot of UI on other boards without anyone realising. I think to play this method ethically you have to ask about an alerted 4
♣ bid as a matter of course. When I played something similar (double here would be "lead clubs" if Swiss/Gerber, but "lead hearts" if a splinter), which was before the previous "no alerts above 3NT" regulation, I did so.
lamford, on 2015-March-14, 13:49, said:
If 4C is natural, which is the only non-alertable meaning of 4C, then double would be takeout. East had no obligation to ask whatsoever. NS had an absolute obligation to read the alerting regulations and follow them. I get irritated when we have an auction 1C-(Pass)-1H-(2H) or 1C-(Pass)-1S-(2S) and the opponents ask "What is that?". "Natural", I reply, "which is why I didn't alert it".
That's not quite an equivalent situation. I wouldn't bother to ask there, but I would ask about 1
♠ - 4
♣ (no alert) because I know the relevant regulation is fairly new.