My return for 2008 or 09 was a mess. I had one 1099 I never received from a former employer I'm convinced was trying to screw me, I had one 1099 sent to a former address and a debt forgiveness 1099 from a credit card charge off. I got a packet from the IRS listing the adjustments, what they proposed I owed and very clear and detailed instructions on how to respond to each of the three changes.

Incredibly easy to resolve the entire ordeal within weeks, including full payment.

I have no doubt that if the IRS truly made it a policy to extract as much money from everyone as they could, they would have just audited me and nit picked every math error ad nauseum until I was drowning in penalties and interest.

This is part of why I have a CPA now.