You can see the email, because I only signed it.
Signing it verifies
that I am who I say I am. NonvocalScream at WMF projects.
Can't you sign it with just a signature? That is, something which goes
at the bottom of the email? The line at the top is completely
pointless - if I care about whether or not an email is signed, I'll
scroll down to the bottom where I would expect to find the signature.
A correctly formatted signature can be hidden by most email clients, I
believe, then you wouldn't be annoying anyone.