I'll start with saying yes I do believe he jumps in at certain times to do things but it is only on his limited basis because he can't just always jump in It would end up throwing to many other things out of balance.
What does this even mean?
Haven't you read god's best-selling memoirs? Every time he steps in to do something he screws something else up. The g-man can't fix one thing without thoroughly breaking something else (assuming he even fixes the thingie he intended to fix in the first place). He's kind of like a cheap auto mechanic.