[bob100147]

You are playing precision,your partner opens 1C, and RHO doubles showing the majors (Mathe). What is a good structure for responses? Double to show 5-8? Are 1h and 1S natural? What do you do with a balanced 9+ but no stopper in at least one major?

[straube]

Sorry if this isn't a true answer to your question, but I'm suggesting you ignore the double. I've had someone overcall 1S on a 3-cd fragment and it seems to me that folks might just try to steal the majors without particularly good major holdings...like 4/4 or even worse. I've also seen one partner think they were playing Mathe and the other think they were doubling to show clubs.

Assigning meanings to responder's rdbl and pass seems like a good idea, but if you do so, then you have to make sure that you understand the continuations...like which bids are forcing, etc. I think I'd assign rdbl and pass the same meaning, no matter whether dbl showed majors or two suits of the same color or a big hand or clubs or whatever. Yeah, you could optimize for every single meaning, but I doubt it would be very worthwhile to do so.

[SteveMoe]

Agree with Straube.
One alternative that is simple splits the 0-7 HCP range into 3 parts:
Pass = 0-3
1♦ = 4-5
Redouble = 6-7
Play all responder suit bids as natural 8+. Systems still on.

However over Mathe 1N (ostensibly for the minors) we play our NT systems:
2♣ = stayman
2♦/♥ = Jacoby Transfers
2♠/NT = transfers to minors (Asking Partial Stopper; showing Jxx or Qxx)[You can choose to turn this off]
Partner can respond with NT hands or Major hands, ignoring the transfer to one major if holding the other, etc.
3♣/♦ is GF NT Stop
Double is penalty [Hxxx+ in one or both minors]
3N promises stoppers in both minors, and tends to deny 4-card majors.
All other Major bids would be to play. 4 minor jumps would be Super 4441 hand.

BTW we do the same thing if they overcall our 1NT opening with 2NT. Works like a charm

[bob100147]

Thanks very much. Both suggestions are very helpful.

[mycroft]

Remember to know your 5th-hand agreements as well - Mathe itself (especially the "majors" double) isn't very disruptive. 3M by fourth-hand is - even 2M is.