It's very possible to use a tool for a year or 10 and not be quite familiar with it's operation. You have to actively make the effort to learn new things to learn new things.

Well, I did manage to get through the first year or two (not 40hrs per week but close) with blissful ignorance of what vim was capable of. Only then did I start picking up new commands beyond the basic insert, append, delete stuff. And even much later did I really grasp vim's concept of text-objects. Of course, this was absolutely the wrong way to go. Would I have spent more time upfront learning, my productivity wouldn't have sucked as much. But then again, typing usually is not the bottleneck.

What I'm trying to say is: Yes, you can very much get through a year or more of using vim without leveraging it's power. (And you probably will, given how much there is to learn.)