It happens often, that we should open 2♣, which brings us to a very high bidding level, and this is a bid disadvantage of the system. If we want to raise our partner later, we simply don't have enough bidding place, if we are a bit unlucky. Let's see, why is it so, and what can we do against it.
If our bidding goes like this:
We are in great trouble, if we want to raise this hearts so, that partner understands, that we are raising him wuth a strong, slammy hand in a forcing way. The reason is that all bids are natural to that, therefore we don't have space to raise heart so, that partner doesnt pass it with weak hand. To jump higher with a hand if opener has very strong raise is still worse, we have to guess very luckily later, not being able to ask any questions from responder's strength and keycards.
Therefore I have the following idea:
We should bid 4♣ in this situation as opener to show a minor suit with at least 4 cards and unbalanced hand, and our 4♦ bid should mean at least slam interest in heart, despite, responder may have complete 0 strength in this situation. 4♥ is a minimum opening with heart fit.
Important warning: Although it would be fine to use the lower suit for fit, because than responder could give 4♦ last train bid if he has a King or better in his hand, we cannot use it, because responder needs this 4♦ bid to ask our minor to the 4♣ bid, and it is much more important, that having a last train here.
So my opinion is, that
should mean, that opener has a minor suit, responder can ask with 4♦ if he is interested to play this, and later we can use our slam bidding assets, and 4NT bid will be natural, not forcing, so as our 5 minor bid is.
Slam bidding assets mean, that responder can give relay RKC here and slam bidding system on later.
|4♦||Relay, asks for the minor, to that 4♥ = ♣, 4♠ =♦|
|4NT||I am strong, but I dont want to play opener's minor|
and here is how we sould raise responder with a forcing bid:
To that responder bids 4♥ with a very bad hand, and goes to slam with an Ace or a useful hand, because opener could have said 4♥ with a minimum opening and fit in ♥.
Important warning: If responder goes to slam in this situation, and gets the information, that all keycards and the Queen of hearts are also in our hands, should show it to the opener with a relay bid, because we can easily have grand slam here!
If opener needs something from responder to play slam, now can pass 4♥ sign off, and he can use slam system other ways.
I suggest playing the following slam system:
|4♠||RKC in ♥ with no void|
|4NT||RKC in ♥ with ♣ void|
|5♣||RKC in ♥ with ♦ void|