What are some theories and reasoning behind why you think site injections would or wouldnt cause localized growth?

I remember reading this one. . .

Stretching the fascia out and making room for more muscle growth (although i think youd need more than 1cc to get any kind of fascia stretching action)


Also, i have been told you can inject in different areas of the same muscle you have hit, a few inches apart
Example: all the way up the outer part of the quad (vastus lateralis/quad sweep). (NOT different heads of a muscle)