[steve2005]

Question after u have overcalled 1S. (1C)-1S-(2C)-X What should it mean?

Have another meaning please comment and I will add.

[aguahombre]

I am suspicious that we are not being told something about the 1♣ opening bid, because this question is under non-natural system discussion.

[steve2005]

its the transfer to diamond option that is not natural

[apollo1201]

Supposing all the rest is natural, X is likely understood as a t/o for the reds (or could be either red with a S tolerance as a back up in case pard bids the other) with decent values considering the bidding (good 8 at least eg Qx Kxxxx Kxxx xx or Kx QJxx Axxx xxx).

[wodahs]

I like playing transfers there, with X = diamonds, 2♦ = hearts, 2♥ = constructive raise, 2♠ = competing.

That's very useful when responder puts some pressure on with a (3♣) or (4♣).

The problem of course is potentially missing a 4-4 heart fit. To minimize that chance, we tend to X instead of overcall with most (54)xx hands, and we play Raptor so if partner has shown a minor, say here (1♥) 2♦ (2♥), not having overcalled 1NT he will rarely have 4 spades.

[BRBanger]

Transfers are pretty, but I agree, we DO need a bid to show 4h. I'd like to include a voting option where the double shows 4h, or maybe a decent spade raise (with 2S as weaker). Happy to use 2D as a transfer, or to swap 2D and 2H.