OK.
Maybe.
I wrote earlier that I'd finally figured it out. I think, on my first pass, when it wouldn't let me enter "UNKNOWN", I entered 0. I seem to recall that it wouldn't let me leave it blank but I could be wrong. When I entered 0 and TT computed that nothing was taxable I probably went back and put the full block 1 amount in 2a.
I can't overemphasize that TurboTax needs to allow the user to enter what the form reads. Expecting the user to go with blank (even if it allows that) is NOT a good solution. Block 2a is NOT blank. It should allow "UNKNOWN" and then do as you say it does if one leaves it blank.
