Notching Marijuana Stems

I recently heard about notching the bottom of the stems before harvest because the plant will think it is about to die and suck up all the thc from the roots.
I skimmed through the 101 asked questions and also googled it.
I haven't came up with anything.

Anyone heard of it?

THC doesn't exist anywhere in the plant other than in the trichomes. There's nothing to suck up.

I've heard Mexicans used to do it to there Acapulco Gold and what not. I've also heard of nailing nails into the stems but personally the only way i could think logically to stress them would be 24 dark hours before harvest or water deprivation (though i havent tried any of these methods this is what i THINK) personally i think if you show ur plant more love than hurtfullness u'll get the best harvest, but thats just me,
pacman

I'll experiment with notching after my first few grows.