No. Do not send them your 2014 return. You are correct that it very well may cause confusion. Simply explain that (at least part) of the reason you are amending is due to the changes from amending your 2014 return. They already have a copy of it, if they want to look at it. And if they want more information from you, they can, and will ask for it. A person at the IRS has to go through everything you send. Don't send "all possible evidence". Send them the necessary supporting documentation.
