Thank you for your efforts. I saw the "distributions from multiple payers" language also and thought the same thing until rereading the new instructions. I believe that other specific language on Line 4a excludes many specific distributions from being entered on line 4a (specific exceptions are made in the recently released instructions for Form 1040). The IRS changed the entries from previous years centered on the taxable-nontaxable distinctions; now line 4b is taxable and line 4a is certain specifically designated distributions.
For example, a pension/annuity distribution for me appears on line 4a (mostly but not totally taxable); two other distributions from an IRA and a 403(b) plan do not. Line 4b has the taxable portion of the pension/annuity distribution and the two other distributions.
The IRS language is very confusing. I think that Turbotax has it right on This issue.
There are several other discussions of this question in this online help section.
Best of luck from another frustrated filer.
