I wonder if that remapping also allows you to use ctrl-i to get out of insert mode. If that's the case, you can switch between the two by pressing i and ctrl-i.
Well, the article says: "There is no way to distinguish between the Tab key and Control+i. It’s not just ‘the same’ as Tab, Control+i is Tab." So you'd be mapping Tab to Escape to get out of insert mode.
