What about it is most likely a lie? I've had dreams go lucid. I mainly want to use them to practice physical skills in the dream world and have them transfer to real life. I remember ready a study about it.
It haunted me for some time after because I never expected something like in the movie inception to be possible in real life.
A study to test this would be simple - test skills level at something (e.g. chess), and then have the study participant study "in their sleep" for a month. Test again. It has never been done. Not even close. As it has never been done, I strongly believe you are misinterpreting / over-stating your results.