you know I always call it a filter too.. no clue why I called it a crutch now.. might have been an easier search term.. I heard an Auzzie say it once and it was what it's called in many places.. I was trying to fit in and you called me on it..The use of the word crutch doesn't make much sense to me when speaking in terms of smoking a joint, it would seem to me that you would need the "crutch" after smoking .
I've always called it a filter, tomato...potato etc.