I was waiting for you to contribute to this thread. Quoted for everyone to re-read.A couple of people had good points: Notably Mr. joey54's remark about consistency and eating and Mr. Acress's remark about the genetic elite growing from almost anything they do.
But there is quite a bit of misinformation.
BOTH high and low reps can stimulate growth (PROVIDED that the caloric intake and rest are there to begin with). Muscle is muscle is muscle. If 8-10 reps makes your chest grow, it will make your legs grow. If you are growing everywhere else but not legs...then you are doing something wrong when it comes to leg training.
Also I disagree (mostly) with high reps as some cure-all. The original concept of the 20 rep squat was not about growth per se (although it does a good job) but about really pushing yourself and breaking past mental barriers. You'll notice that no one really touts 20 rep bicep curls, bench presses, tricep pressdowns, deadlifts (although a few people do this last one). Why? Because it's not about growing from 20 reps it's about challenging yourself. 20 reps is not some magic number (19 or 21 or even 15 would likely work as well).
Intensity, consistency (in and outside the gym) and self-discipline are all far more important than any number of reps or sets. When everything is taken into account the volume (for the average natural trainer) just isn't that important.
When everything else is in order, then the amount of volume (unless you are doing ridiculous extremes either way) is not a huge factor unless you are a highly advanced trainee.