Beware the Attack Basset
Sometimes it is a delete button and other times it can be something else. The function of the button (and any of the other colored buttons) depends on the context in which you are using it.You are right. But here is a photo showing the delete button.
One of the places that it doesn't work is in the context of a program that you've just watched using the DVR function on the HWS (and probably others). There you must navigate using cursor keys to a delete menu option.