Vampyr, on 2015-April-20, 08:53, said:
Under this (1997) law you were allowed to change a bid based on a slip of the brain and play on for Average Minus. This law was widely ridiculed and did not make in into the 2007 version.
It is clear that the simple omission of this law does not suddenly mean that brain-slips can be corrected with no penalty.
You are confusing things. The old Law 25B2(b)(2) was about changing an intended call. Law 25A is about changing an unintended call.
You splintered with 4♥ in response to partner's 1♠ opening. You did so consciously and decided for 4♥ since you valued your singleton and then you made the bid. Once you had made the bid, you figured out that 4♥ wasn't a splinter but natural. That is not a "slip of the brain" that is a bidding error.
Under the old Law 25B2(b)(2) you were allowed to change that intended call and play for Ave-. Law 25A has nothing to do with it, since you consciously bid 4♥. 4♥ was your intended call.
Law 25A is not about correcting intended calls. It is about calls that one never intended to make. Law 25A is not for the system mistakes or regrets in hand evaluation, like the old Law 25B2(b)(2). It is for when one never intended to bid 4♥, but somehow the 4♥ card is lying on the table. And it doesn't matter whether the 4♥ card landed on the table because of a coffee stain or because "a voice made me pull the 4♥ card". In both cases one never intended to call 4♥ and law 25A applies.
And that is very different from deciding to splinter and then regretting it (old Law 25B2(b)(2)).
Rik