While I have never known the IRS to prosecute anyone for filing without a form and amend later, you do sign a tax return (either on paper with pen and ink or electronically with a pin) under penalty of perjury that the tax return is complete and correct to the best of your knowledge. Since you know that it is not complete then you are committing perjury if you file without a necessary form.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
