Probably within the last year, I came across a recent textbook or textbook-style presentation of quantum mechanics, at the freshman level, that introduced the subject from scratch using decoherence. I think the text was online and not paywalled. Now I can't remember where I found it, and I can't seem to find it by googling. Can anyone point me to it?
I finally remembered what book I'd had in mind. It's Griffiths, Consistent Quantum Theory, which is available in print and for free online. Although it does have a chapter on decoherence at the end of the book, my memory was wrong. It focuses on the consistent histories approach, not decoherence.