How does taxonomy breadcrumbs interfere and/or work with the normal breadcrumb ?

If we have regular pages that are not part of any category scheme how does the breadcrumb function ? Can we use both breadcrumbs ? Who ever invented this taxonomy stuff was really smoking too much crack, it needs to be brought back to simplicity - pages are pages, posts are posts and categories are just plain categories, easy 123, why do they make simple matters so complicated.