This is a feature, not a bug, in the current TurboTax implementation.
The developers believe it is correct under current IRS guidelines (the
problem is that the IRS combined two lines into one on the "simplified"
Form 1040, and TurboTax has decided on a peculiar implementation).
Apparently, the IRS has ok'ed this implementation, despite the fact that
it seems counterintuitive. As long as the taxable amount is correct,
no issue.
