Obviously the IRS doesn't even know their own policy. No surprise there. There is a certain schedule that you fill out when you have foreign earned income (I can't remember the schedule now) where you report your foreign earned income, plus any credits for eligible taxes you have paid abroad.
Not filling out a 1040 does leave you open to the IRS questioning that you might have been earning income and then attempting to come after you while you are abroad. It is your responsibility to report that you have not been earning anything.
Also, if you have over the equivalent $10,000 in foreign accounts at any point during the year, or one you have control over (like a joint account with your spouse, etc) then you have to fill out a US Treasury form stating what accounts you have and where.