Pollen can travel up to 2 miles, idk most people dont like breeding with herms bc they pass that trait to the offspring 50% of offspring will be herms. If the herm shows in an enviorment in which you are trying to grow sensi and it herms that means those conditions are going to bring out the herm evry time. You may be confused and even say that the pros use herm pollen with no negatives, thats bc they force the herm either with CS or other means and even then they dont pollenate the same plant they just harvest the pollen and pollenate a different plant. Hope it works out for you either way good luck with that