I'm not sure that would work - in my experience, the reason that they are still on IE6 is they have hundreds of seats to upgrade and, more importantly, the entire network has been totally locked down over the years to deal with IE6 issues - giving the network admins a known surface to protect.

For example one of my client's clients has a rule that disallows Ajax HTTP POSTs - when I asked why they said "security - and it's not going to change".

So upgrading isn't a technical or a feature request - it's a total mindset change.