lamford, on 2017-October-09, 11:25, said:
I don't think the TD needs to know what went through his mind before allowing the call. He just needs to know if the meaning of the replacement is consistent with what the original call could have meant in some other auction.
Suppose he thought he was opening 2D as multi, showing a weak 2 in an unspecified major. He replaces it with a transfer to the major he actually has, and everything proceeds normally.
If he meant it as Flannery, and they play Smolen over 2NT, he can replace it with that.
He might have a hand that they don't have a method to show over 2NT (e.g. a Flannery hand when they don't play Smolen); in that case there might not be a comparable call.
I'm a little unsure about the Flannery->Smolen replacement, though, because it's not a single call but a series of calls. It starts with Stayman, which doesn't show anything in particular. The CC definition says that a call is comparable if it asks the same question, but Flannery doesn't ask anything.