I have the exact question. It would seem sufficient to file just the 1040X along with schedule(s) and explanation reflecting why and how the return is being amended. On the other hand, the Turbo Tax recalculates the numbers on the original tax return to take into account the changes made by the 1040X and its associated schedules. So, unless an expert (which I am not) chimes in, in an exercise of caution, I'm going to mail the 1040X with attached schedules, and then also include the changed 1040 that now has updated numbers. As a comment, it is annoying for there to be ambiguity where it is so ez to make something clear (file just the 1040X, or file both the 1040X and the changed original 1040).
