Ahhhh, but it CAN happen!!
If you read anything on Myostatin blockers and inhibitors you will see that animals like those Belgin Blue Cattle and Gorrilas are much closer to their maximum skeletal muscle based on the the extream low amount of free Myostatin. Now you look at mice as shown in the studies and they are no where near their max skeletal muscle maximum as shown by the extreamly high amount of free Myostatin. The studies showed that when they blocked only 50% of the Myostatin in the mice, that they doubled in muscle.
Now based on that, if you look at how much free myostatin is in the average human, you can easily draw the conclusion that we could very easily double our muscle mass by blocking or eliminating even 50% of our Myostatin.
I'm not saying this is safe or wise, but it IS possible!!