I agree it seems surprising, but the amount that is feeding to line 4b on form 1040 is correct (i.e., in my example above, line 4a on 1040 is 7,000 + 7,000 + 10,000 = 24000 (two Back Door Roth's plus Inherited RMD, and line 4b is 10,000 (just the Inherited RMD) . So Form 8606 is wrong, but weirdly, doesn't add up, I guess.
But I also agree... the "fix" doesn't stick... if I save the file and re-open, it comes back. So I'll have to amend either way. Fortunately, I did a compare of the PDF output of the original PDF and the "fixed" one and the 8606 form is the only filing form that is different (the IRA Information Worksheet is also different, but not filed).
So I suppose as soon as the IRS publishes 1040-X, even if TurboTax doesn't fix the issue, I can just amend and file that one form. But it'll be easier if I just can use TurboTax.
