The proof of pudding is in eating. To prove the detrimental effects of filler words, an example may be the pudding you can serve your audience. Here is a script based on this idea. Have a look.

“Toastmasters is like, basically, a fun place to learn public speaking you know.”
If we remove three words from this sentence – like, basically and you know; the sentence still remains complete and sounds more assertive.
These three words add no value to our message and lengthen it unnecessarily. Such words are called as filler words. Ah, umm, err, like, actually, but etc. are the other filler words that we tend to use unintentionally while communicating. As an Ah counter today, my role is to keep a track of all the filler words used by the speakers today while on the stage. I will note their usage and come back with my report towards the end of the meeting.
Thank You