The TurboTax worksheet that is new for this year (1040 Wks) is in bad shape (broken links to data sources and incorrect references to the new Form 1040 Line numbers.)
That appears to be the root cause of the amount on line 4a being smaller than the amount on LIne 4b, which can't reasonably be the intent of the IRS on this new Form 1040.
This has been reported to TurboTax by myself and macuser_22, but even if they fix it, they may fix it in a way that leaves the same problem - because there are a number of people, some who work for TurboTax apparently, that subscribe to the notion that a literal interpretation of the IRS instructions requires this nonsense result on Line 4a.
They "explain" that multiple IRA's would require a total distribution on 4a, and so would multiple pensions, but a single IRA plus a single pension isn't really a multiple distribution, even when they are now reported on a single Line. It is a mess: If you want more immersion in this mess, follow this other chain of messages:
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