I would argue that it is a possibility. Not only can it be done by taking advantage of the subconscious mind, the theory of clinical hypnotism and neurolinguistic programming works off the assumption that a persons mind can absorb ideas.....type into youtube simon pegg and derren brown BMX for a perfect example of the above.
I know of a few people who have written techniques to influence anothers thought magically, some were respected occultists....I believe I recall florence farr writing such a technique (it was definitely a golden dawn member).
Sadly I haven't tried these techniques and so can't give my personal opinion or experience on them.
As for instantly making someone shut up, isn't that best done mundanely by asking them? I personally wouldn't wish to control someone else, if I was annoyed I would politely confront them, or leave. If they followed I would confront them more forcefully...