From time to time a corporation or its advisers will consider taking a position on an income tax return which is advantageous in the year for which returns are being prepared but inconsistent with a position taken on a return for a prior year, perhaps a year with respect to which the statute of limitations period for assessment of additional tax has run. Even where it is reasonably clear that the earlier position was erroneous, the IRS has a powerful argument against the inconsistent position in the later year, namely, the so-called "duty of consistency."