Can Mail.app be configured to insert a blank line before the text of the previous message in a reply?

Currently, a reply window contains this:

*new message text starts here*
... old/previous message text starts here...

What I want is this

*new message text starts here*

... old/previous message text starts here...

Not ideal but:

Go into Preferences: Signatures, create a new Signature, erase the name and e-mail address, and hit Enter once to create a blank line. Then check the "Place signature above quoted text" box.

Note: once a signature has been saved with actual text, Mail won't let you blank it out, so make sure you do this with a new sig, rather than editing an old one.

I believe you can configure the free QuoteFix Mail plugin to do what you want.