[Flame]

You hold a 6♠-5♥ 15 hcp hand, certently offensively worth the 1♣ opening.
You play relay after 1♣.
Suppose you open 1♣ partner response 1NT showing a diamond suit, would you keep relaying (2♣) or you will show your hand (can you do this in your relay system).
Is it better to open it 1♠ and then make a strong bid maybe 4♥ than getting into an unplesent 1♣ relay when partner show his hand which isnt what you want ? will you dare do it with 16 hcp too ?

[Free]

Depends on the hand, HCP aren't everything... If you give me a lovely KJxxxx-KQxxx-K-K I would definitely open 1♠. However, a AKTxxx-AKJxx-xx-void is imo better opened 1♣. These are 2 extremes, so I guess you have to look at one hand at a time and make your decision.

If you can reverse the relays, you should do it imo. You are a minimum hand, you probably have good playing strength and partner will be able to judge better if slam is possible or not.

[helene_t]

I can't show this shape so I'd have to relay. This is not so practical since we may allready be too high when I discover that p's honours are badly plays. Alternatively, I could show a 5-5 or 6-4.

[hrothgar]

Reverse relay is a fairly complicated topic.

One school of thought (with which I agree with) suggests that a low level reverse relay in a game forcing auction should be used to show two or three suited hand with shortness in RR's suit. The goal is to identify a misfit ASAP and steer the contract towards 3NT. if you have one hand with 5-5 in Spades and Hearts opposite another with 5-5 in the minors, your trick taking capability is severely curtailed. Equivalently, if you have a three suiter with shortage opposite partner's long suit the value of your hand goes down a lot.

Here's one simple structure that can be used after a strong club opening and a 1N response promising Diamonds. it can (easily) be modifed over a response that shows another suit

2♣ is the "normal" relay
2♦ = Reverse relay, 2 suited, S+H (0-1 Diamonds)
2♥ = Reverse relay, 2 suited S+C (0-1 Diamonds)
2♠ = Reverse relay, 3 suited (0-1 Diamonds)
2N = 4 Hearts and 5+ Clubs, 0-1 Diamonds
3♣ = 5+ Hearts and 5+ Clubs, 0-1 Diamonds
3♦ = 3-5-1-4 shape
3♥ = 2-6-1-4 shape
3♠ = 3-6-0-4 shape

If you follow this advice, then you should be reversing the relay with 0-1 Diamonds. Otherwise, you relay.

(Please note: Even with the explicit agreement that the Reverse Relay shows Diamond shortage, the auction is still really cramped. If you start throwing in lots of superfulous hand types - for example, you allow a reverse relay with long Diamonds or some such - ou won't have nearly enough room to figure out whats going on below a reasonable safety level. I'd strongly recommend looking at your reverse relay structure and checking how safe it actually is)

[Flame]

Thanks everyone especially Richard, we will implement it . we are adding 7 card suit to the RR by bidding 2D and then 2S.