So a quick clarification, Genetic Drift is misused in the cannabis community. In science it refers to shifts in the gene pool when a portion of a population is suddenly removed, reducing genetic variation or shifting it towards certain mutations that survive the shift in lieu of the ones that disappear.
When people describe "genetic drift" in cannabis they're actually referring to epigenetics theory, which is a theory that questions whether you can force phenotypical changes to alter inheritable gene expressions without altering the actual genetic make up of an organism.
Im not a botanist so you'll have to bear with me a bit, but essentially the idea is that if a plant has a gene that isn't triggered, and then you force it to trigger so that it shows a different expression, will it's offspring show the new expression as well. The argument usually comes up in the cannabis world when discussing intersex traits due to the long held belief that if you force a plant to show intersex traits for breeding its offspring will be more likely to be intersex, but it could apply to the stress applied to trying to keep a plant alive and a certain size for an extended period. Essentially the idea is that you aren't changing the genetics, your just triggering a latent gene that was already there, changing the phenotype of the plant, and once that's done, any clone taken would obviously show the same phenotypical change.
It's all a theory at the moment, so I'm certainly not stating the above as factual, but I also think we need to keep an open mind on the discussion.
Ive been researching this a lot lately because I'm having a weird experience with my Mass Super Skunk cut. Mom underwent a really stressful period, then the next cutting I ran grew completely differently than the original. Same smell, same taste, but the structure and yield were worlds apart from the first couple runs. I attributed it to my growing so I tried again, but the same result. Now I'm flowering the mom and again, same result. The terps are the same as before, but the plants structure is completely different and the yield is immensely diminished. I'm still not sure what happened, but trying to figure it out basically taught me that I don't know half what I thought I did.
Anyways, sorry for the wall of words guys lol. Just obviously a topic I've had on my mind.
Edit: removed a couple posts I apparently stoney started and never posted lol