[aflag]

I'm not sure that's really true. You tend to think more or less in the terms of the language you speak most of the time. For example, I lived in the US for one year and, when I got back to Brazil I'd often think like "I like this better", wheras in portuguese you'd say something like "I like more of this". My point being that we adapt to think how we speak and write, so that's not really the issue when writing down your thoughts.

I think the hardest thing is to be coherent, when you think you often skip steps that you look with greater care when you write. It's not uncommon that some of the steps you're skiping are crucial ones.