If a taxpayer applies for a mortgage and submits the tax return with Form 1040 unsigned and Form 8879 signed, I expect the taxpayer will eventually have to sign the tax return to get the loan.  The E Signature copy Form 8879 is unsigned by the Taxpreparer.

So, in the end, I have an unsigned PDF of Form 1040 and Form 8879 that is signed by the Taxpayer but not the tax preparer.  Lots of loose ends.

I think the Tax Preparer should also E-sign Form 8879.