Thank you for your reply :-) I was wondering if i was missing anything.
In the future if i need to use inheritance, i might put this timer as a simple attribute, and pass it to my objects from the client code. It's giving some non-related job to the client, but it should do the trick.
I'll keep an eye open, in case you created a new MooX module. Sorry i cannot help : i don't have the skills nor the time to develop them right now.
OK, MooX::ClassAttribute is now on CPAN. Subclassing Method::Generate::Accessor to generate class attributes was relatively easy. The hard parts were getting class attributes defined in roles to work, and getting Moose inflation going.