@johnmcnett1 - it depends if the form itself has an explanation section.  what is the explanation you think you need to add to the return? 

Without any personal information like your Social Security number etc., please explain what remarks you think you need to add to a tax return.

TurboTax provides for entering an explanation where it is required by IRS rules. The IRS does not want explanations that are not required by the rules. The IRS instructions for Form 1040 say "Do not attach correspondence or other items unless required to do so." If the IRS has a question about your tax return or wants more information, they will send you a letter asking for it.