[dave_beer]

I think it is close between PASS and DBL with the East hand but DBL is not for penalties in my style. I have a bad strong NT and the wrong number of ♠. If I have a penalty double I just PASS and stay fixed.

If East doubled I could PASS hoping that we don't have a slam and that the penalty would be larger than our game. I have a better than expected hand but my values in ♠ are not working and if we need a ♣ finesse it is more likely than not going to fail. However, slam is still possible so I would bid 4NT asking partner to bid a suit but intending to convert 5 of either minor to 5♥. To me this suggests a good 5♥ bid giving partner a little leeway with a minimum hand.

If East passed I would also PASS with the West hand.

[pescetom]

miamijd, on 2017-June-07, 15:58, said:

The way I play (which I think is the "standard" treatment nowadays) is that X is takeout and 4NT is two-suited (any two suits). If you have a strong hand with lots of spades, you end up having to pass (but honestly, how often will this happen). Of course, partner may pass the X of 4S for penalties even though it's a TO X, and he will most of the time.

Please could you explain further how the two-suited bid works?
Would you bid 4NT as East in this example?
What would West do if you did, and on what basis?