Many years ago I prepared a form which I sent to anyone requesting information from me. It was to be signed under penalty of perjury. Nobody signed it. In fact, no one paid it the slightest heed, and I have stopped using it.
Forms are funny things.
When you get one, you are expected to complete it. If you send one, you can be assured you are wasting your time. Most of the forms you receive are from the government, or an agency which is authorized to demand information from you pursuant to some law or other. They may contain dire warnings of your fate should you ignore them, or fail to give them proper respect. If, for example, you cross out the jurat on your income tax form that states that you completed it under penalty of perjury because you took no oath, and therefore couldn t have committed that crime, or because you cannot swear to the exact size of your income in terms of undefined dollars, you will be threatened.