I was thrown a bit when he say's "To code in Vim, you have to keep Vim in your head just as much as the code that you’re editing. You have to constantly think about what you’re doing." I have a few coworkers who work completely in vim while the rest of us use Visual Studio. I ask them questions about vim usage and usually they have to think a while about what they actually do because using vim is second nature to them.
I do not have to think about what I'm doing in vim, when it comes to normal text editing.
To be quite honest, getting up to normal-editor level with vim shouldn't take more than a month to become comfortable. Learning to move, yank, paste, and navigate windows is not hard and you really don't have to think about it.
More advanced usage I have to think about, but that's no different than if you had to think about what you were doing in sublime when you clicked search and replace and started typing in a regular expression.
