President Obama's re-election campaign continued attacking Mitt Romney this weekend over whether he retained control of Bain Capital after 1999, when the GOP candidate says he left the private equity firm he founded to run the Salt Lake City Winter Olympics. Last week, The Boston Globe reported that Bain continued to describe Romney as its "sole stockholder, chairman of the board, chief executive officer" until 2002, three years after Romney says he made a clean break with the firm. Obama, who's been hammering his rival on Bain for months, says Romney should clear up questions about his tenure at Bain because he's basing his economic credentials on the work he did there. Romney supporters say Obama is trying to distract attention from the economy by playing "small-ball politics." Meanwhile, top Romney adviser Ed Gillespie say his candidate left Bain thinking he would return, then changed his mind and retired "retroactively," dating back to when he took his leave. Does it really matter exactly when Romney stopped calling the shots at Bain? Here, four reasons it does, from both parties' points of view:

1. Obama's attack ads focus on what Bain did in the gray years
There's a simple reason why it matters, especially to Team Obama, whether Romney left Bain in 1999 or 2002, says Benjy Sarlin at Talking Points Memo. The Obama campaign has hit Romney with a barrage of attack ads "based on deals Bain made during that gray period, 1999-2002, when Romney was in Salt Lake City." Linking Romney to those years allows Obama to accuse Romney of "profiting off companies that outsourced, laid off workers, cut benefits, or made Bain money as they went bankrupt." And if Team Romney wants to successfully absolve its candidate of blame, it needs to define the documents that list Romney as head of Bain in that period as mere formalities.

2. Bain was involved in abortion during those years
There is a "deeper answer" to the question of why the 1999 date matters so much, says Sherman Frederick at the Las Vegas Review-Journal. Team Obama really wants to link Romney to "one Bain investment in particular" that someone at the private equity firm approved during the disputed period: Stericycle, a medical waste company. Stericycle, among other things, disposed of aborted fetuses, and CNN's John King has reported that the Obama campaign is hoping to make this fact, and Romney's alleged connection to it, a "last-week campaign bombshell."

3. This shows Romney and ordinary Americans live in different worlds
Even if Romney stopped making day-to-day decisions for Bain in 1999, the idea that Romney could pull in a $100,000 salary, keep his title, and own a company for years, while doing nothing to actually manage it, sounds unreal to your average American worker, says Garance Franke-Ruta at The Atlantic. "That is not how most workplaces run (those no-show jobs on The Sopranos excepted)." If Romney is forced to explain his murky departure from Bain, his perfectly legal offshore accounts, and other financial details, it will only drive home the message that "things work differently" for super-rich business tycoons like him.

4. It is something to talk about instead of the economy
Team Obama has gone so far as to suggest that Romney might have committed a felony by telling federal regulators (via documents Bain filed with the SEC) that he was still Bain's CEO  after he retired, says Ed Morrissey at Hot Air, but several fact-checkers, including CNN's, have debunked this "ludicrous charge." Romney "left Bain in a big hurry in 1999" to rescue the Salt Lake City Olympics, and it took some time for Bain to get its house in order in his absence. End of story. The only reason the Obama campaign is continuing with its "pathological" lying about this is that "it beats talking about the economy, jobs, the deficit, and anything else that actually matters to voters."

Read more political coverage at The Week's 2012 Election Center.