I was surprised when this was revealed a couple weeks back. Not that Trump mislead us, but that no one at the IRS "leaked" that it wasn't true. This will of course be used against his campaign. And while Trump is likely working within the tax code that was designed for the wealthy, Joe 6-pack is still going to have a problem with a billionaire not paying taxes. Even if Trump lost money, and had no income to tax (within current tax code/law), many people won't understand beyond "Mega-Rich guy not paying his fair share".
It was a lie that didn’t need to be told. Those are bad lies.