Yes the Black Friday and EPP prices can be combined, I put some things in my cart to prove it to myself. If you are going to try and get this deal in the physical store, print out the prices from your EPP website and take it with you. Last BF the store manager would not honor both. Nice to have the proof in your back pocket in case it comes up. Have fun!
Note to EPP users, you have to click on the Red Sale Event graphic in the middle of the front page to see the stacked pricing!