Decided To Try The Idea Don Brought Up - But In A Different Way

Interesting idea John.
What are you using for your email subject line?
Are you trying more than one version? (split test)
Have you considered doing a mockup of some kind, "this is what your site could look like?" in the email. Might increase conversions if they can see what the site might look like instead of trying to imagine what it is you're talking about when you say "mobile friendly".