a lot of the super high thc samples probably come from a very small percentage of growers. if you give a shmuck a seed with genetics potentially capable of 30% thc, the chances of him achieving that are very slim. on the other hand, if you give an experienced, knowledgeable, talented grower the same seed, he just might get there. i've given a friend a seed and started one of the same myself, and mine was twice the size and twice the potency of his (he has been making huge improvements, however, i expect him to pass me soon
)
and how many growers actually get their weed tested? i wouldn't mind, but its expensive, and my area is currently not legal, so i'd rather not have mail coming from weed testing labs. if you had a much broader set of samples for statistics, the picture would certainly change, just not sure how