Though it is no secret that the government has experimented with hypnosis, LSD, "mind-control", and so on, I think most of this stuff borders on conspiracy theory silliness. The whole MKULTRA is shrouded in misinformation, half-truths, and various other kinds of misdirection propaganda.
Here is my theory about conspiracy theories. I think they are manufactured by the very people they allege to be about. In his book, Get Anyone to do Anything
, Dr. David J. Lieberman PHD explains an interesting technique for stopping a rumor in its path, even if it's true. Here is how it works. If you are confronted by someone about a rumor they heard about you, you simply admit to the rumor, and then expand it by tagging on a ridiculous piece of information that no one could possible believe. What happens is that people will tend to disregard the entire thing because they will generalize it all together.
I think a conspiracy theory works the same way. It's perfectly feasible that the government would want to learn new ways to gain compliance from civilians, but there is really no way to completely cover these things up. So instead you just allow the truth to be "discovered", but with that truth you add "facts" about hypnotized assassins, with full post-hypnotic amnesia of the event of course, and for extra measure be sure that some of your agents write some good books about CIA connections UFOs as well as some Reptilian stuff for good measure.
The only people who would believe any of this stuff are those who would pose absolutely no threat to the government whatsoever, while those who could potentially become problematic will tend disregard the entire thing...including the parts that are true. The use of critical thinking will help you make some reasonable assumptions, and they are usually so straight forward that there is hardly any need for "conspiracy" in the first place. Besides, power does what it wants, so why would they have to be so clandestine in the first place. Our real problems are much more mundane. Television, for example...