Putting bay leaves in the water when I soak beans overnight is something I have been doing so long I can’t remember whether it was told to me or I read it. I think it was someone telling me about it making the beans more tender. Not sure if it actually does, but I do know it does something. About ten years ago I was out of bay leaves when I was making congressional bean soup, which I make often. Surprisingly the beans didn’t taste near as good as they normally did.
Now, thinking about it, I actually don’t think it makes the beans any more tender but it does change how easily they absorb flavours. Also the bay leaves do flavour the beans. A little thinking about high school chemistry reminds me that you can change absorption rates of things by using certain chemicals. Something that the bay leaves give off in the water changes the absorption ability of the bean in a good way. Not sure if it does but there is a difference in taste.
Or it could be that I just think it does and don’t want to change what I do when I soak beans. We all have things we do and will not change because it’s the way we do things.