When people say "you know what I'm saying?" over and over when they're talking to you. I like to say, no I don't know what you are saying.
Agreed. I try to be cognitively aware if I slip and use those filler words that don't mean anything.
Back in an economics class several years ago, one of the students in my class had a question about the upcoming exam. Here's part of the exchange he had with the professor that I found rather amusing
Student: So for the test, you know what I'm saying (pauses to gather his thoughts)
Professor: Not yet. (sort of a smug smile)