Hello,
I hope this blog by Aaron answers your queries
https://community.dynamics.com/crm/b/dynamicscrmsupportblog/archive/2012/11/09/email-router-demystified-explanation.aspx
Hope this helps!
Regards, Abhishek Bakshi If you find this post helpful then please Vote as Helpful and Mark As Answer. Check my blog on https://mydynamicscrmblog.wordpress.com/