Even if you do file with the IRS while overseas, it's much more difficult for them to check things. And it could also be that you don't have to file the capital gains exempt things in the overseas territory, which would give you a clean tax bill from there to give to the US.

Either way, it's the article that made the claim that this was something of a tax haven. I don't think anyone here is a tax accountant with enough knowledge to know how that works.