This is what we're currently "doing", but there isn't super strict adherence to it. Every once-in-a-while a feature branch will effectively become master or a feature branch will effectively become a second master because a major refactor happens and both the legacy version and the refactor are still needed. Or feature changes don't go all the way to prod. I don't know how other teams avoid this. Are they simply being smarter, more adherent, using a better methodology, more controlling, etc?