If he forgot to initial a box, John Stewart would have a laugh at his expense and it would underscore the notion that filing is complicated (and should be simplified). But that's about it.

The salient point here is that there is no right answer to even moderately complex tax filings. Ralph Nader did this experiment a while back. The same relatively simple tax filing was sent to something like two dozen IRS offices. Each one checked the filing and weighed in on the correctness of the form. Every office said that the filing was wrong but they all came up with different and widely varying figures for what the "correct" figure should be. I suspect a large part of the reason this guy uses a preparer (software in this case) is so that even if "errors" are discovered, he can plausibly claim that he did the best he could and can expect leniency. (Timothy Geithner, white courtesy phone please.) Think you can just ask the IRS for instruction and/or definitive rulings? They get it wrong, a lot. (http://www.treas.gov/tigta/auditreports/2005reports/20054014...)

Bignum hours and dollars are spent by individuals and corporations attempting to do taxes correctly. The time suck and opportunity costs are massive.