[Salvation]

When people interject “You know what I mean.” in a sentence — usually at the end of a sentence.

[BitWielder1]

“You know what I mean.”

Or "you know" for short, is either a meaningless time filler or the speaker is unable or too lazy to express himself properly.
The listener is expected to fill in the blanks.

[alexander_busek]

When people interject “You know what I mean.” in a sentence — usually at the end of a sentence.

I find that merely sloppy.

"I need you to go over there and be quiet" is much more insidious, since it disguises a demand as a gentle request.

Regards,

[dfwgator]

When someone starts a sentence with “To be honest with you....”, you know they aren’t being honest with you.

[Textide]

Similarly, the use of “Right?” after virtually every statement. I’ve noticed this more and more in training seminars and among the talking heads on tv. I would pay to have someone just answer ‘No’ or ‘Well actually..’ each time.

[TheNext]

These are mostly expressions of human dysfunction, such as, seeking approval, control, fear etc. Which explains why so many attribute the phrases to liberal Democrats.

“You know what I mean” seeks approval from others. It checks for group think approval.