Ya, Id really like Freak to expalin Gregs arms. Only way I see is stretching w/ large oil shots and lots of them, pluss working the hell out of them. I bet that mother has stabbed in excess of 10-15cc at a sit'n in each arm so many times he quit counting.
I bet the volume he has used would make your head spin. 10-15cc nothing--I'll wager he shot 25-50cc or more at a clip. And there wasn't much fascial stretching, I assure you. I'll bet a ton of that leaked into the subcutanoeus fat as well. There isn't an ounce of muscle in those arms--just a sack of scar and old pus.
Along this whole topic, Greg Valentino aside, I can tell you I use the vastus medialis frequently, and it isn't a very large muscle by nature, and it is enclosed in it's own fascial covering. At least 3-4cc per week into each one, over a 24 week cycle, is going to be 72-96cc total volume per cycle. In the last 2 years alone, then, my vasti have seen a total of 288-384cc. I have good legs, and I have good vasti, but my teardrop isn't "unusually" large or out of proportion to the rest of my quadriceps.
Site injections in general are a myth.