Had I misheard her? No, she said it again: "I wonder if yous could just check this?" And again: "I will confirm this to yous in writing."
Although she was clearly in a one-to-one conversation, she obviously felt she was talking to the bank collectively, as it were. So she was using what, in her mind, was or should be the second person plural pronoun. As I left the bank, I found myself asking: "Why not?" There is a clear and certain logic about adding the "s" to "you" to make it plain that you are talking to more than one person. Almost every other language I can think of has it: the French "vous" is not far removed from the Rab C Nesbitt "yous".
I mention the abominable string-vested one as it is undeniable that the word is a favourite tool of people of his ilk. But it is undeniable that it gets over their meaning.
Other English-speakers who are not of his ilk, and not brave pioneers like my bank lady, are reduced to getting over their meaning via pathetic constructs such as "you two (or three or ...)"; or "you lot"; or "yourselves"; or (in America and now imported into the UK) "you guys"; or (in America) "y'all".
It just won't do. And it certainly can't be endorsed by those who should know better. I have a web page in front of me by some academic called Jeff Magnus, which says with authority: "'Y'all' is a contracted form of 'you all' and as such is an acceptable usage. There is no 'yous' or 'youse'. Do not use them."
Pardon? How can an ugly joining-up of two words possibly be more "acceptable" than the simple, elegant adding of an "s"?
I have often taken issue with the school of teaching thought that says street language is just as valid as that of the royal court. Generally speaking, I just don't agree. But for "yous", I'd make an exception. It's just a question of getting used to it.
If Joanna Lumley did use it on stage or if the Queen herself employed it, surely then it would become quite acceptable to us.
I can hear it now: "My husband and I hope yous have had a wonderful year and we wish yous the best for ..."
Well, maybe not. It was just a thought.
Rick Wilson is a freelance journalist.