This is partially why it can be frustrating to work with someone who isn't as good as you are. Things that come easily to you doesn't for others. You sometimes have to remind yourself that things that you consider obvious is only obvious for you.
This reminds me of a story from Feynman where he was with a math friend and they were trying to multi-task. Yet, they ended up going about the two things (counting for a minute while reading or speaking) in completely different ways. (Different enough that one could only count and talk while the other could only count and read.)
