[Free]

(theoretical question)

Suppose that you've played strong two's in the past and you've switched to weak two's a few weeks ago. You hold a classic weak 2 opening in ♠, so you open 2♠. Partner alerts (if necessary) and raises to 4♠ which ends the auction. When asked he explains this as "strong".
At the same time, you have an old convention card at the table, which states that you play strong two's.

Opponents may or may not be damaged by this, this is actually irrelevant.

My question is: can this be treated as a "wrong explanation"? Or is the explanation considered correct since it's the same as your CC and your opening considered a deviation from the system? In other words, do 2 wrongs make a right?

[iviehoff]

The question boils down to whether a director should rule on the basis of mistaken call or mistaken explanation when a player's (possibly) mistaken explanation coincides with what it says on his card.

L 21B1b says: "The Director is to presume Mistaken Explanation rather than Mistaken Call in the absence of evidence to the contrary"

So, assuming the opener tells the truth when asked why he opened a weak two, I think it is likely that the ruling will on the basis of Mistaken Explanation.

[blackshoe]

So do I.

[bluejak]

There are no absolute rules about judgement rulings. Eventually, a TD or AC makes up his/their mind based on the evidence available.

[kgr]

You had the agreement that you play strong 2M, but changed this agreement to weak 2M.
You forgot to change your CC and you opened a weak 2M, but partner explained this as a strong 2M.
I think it is clear that your agreement is weak 2M and both the CC and the explanation is wrong?