True, natural polyploidism is unheard of in nature for cannabis. Colchicine is best used to treat seeds to induce polyploidism, but is a deadly poison and no part of any plant treated with colchicine should ever be ingested for at least one generation. Experiments that I and some of my friends undertook many years ago in the quest for "super pot" led us to believe the risks were too great for the home gardener, the results were highly random and virtually impossible to stabilize in the mother plants or any subsequent generations. If you had access to millions of dollars, a dedicated laboratory, 100s of thousands of seeds/plants and enough patience for years of research, you may get a stable strain. However, all that have gone down this path, that I am aware of, have usually lost funding due to not providing any tangible results. As far as I know, cannabis is limited to about a maximum of physical production of THC of about 30-35%, which means breeders are already knocking on that door with "normal" diploid plants, so the need for polyploids seems unnecessary at this time. Remember too, just THC levels are not what gets people "high", but a combination of many, many cannabinoids working in harmony to combine the "recipe" for "highness". If it were easy and safe, breeders would have been able to bring these "super plants" on to the market long ago. Colchicine is a toxic poison and I would advise against even thinking about using it at home. It is not really a mutation, but gene manipulation and this is the stuff of Frankenstein and science fiction. Never, ever consume anything treated with colchicine, it may cause irreversible damage to your body.
Hope this helps,.....
Organoman.