Well all I know is that my calves used to be so skinny, I wouldn’t wear shorts to the gym. Then I started injecting mostly into my calves, some cycles exclusively into my calves. Winny, cyp, deca, masteron, you name it, it went into my calves. Now maybe it was all the hard work over the years, but now they are one of my best body parts (18.5 inches to be exact). Genetically I had very small calves, but not anymore!
I also have calves that just never responded. Even after running a cycle and training them every day with every imaginable set/rep scheme, they were still only 16".
During my current cycle I included two sites on my calves into the rotation, and hit them quite often. They have each grown an inch in the last 7 weeks. Like Tone said, it’s hard to say with any certainty that site injections really work, but there are many anecdotal reports of success like the ones mentioned here, too many to discount IMHO.