There is literally no reason to take away the double decker taco.  Taco Bell always carries both shells, so why not just continue to let them live together in harmony??  I remember the first time I ever tried the double decker taco.. I think it was the summer before 4th grade, and my life was forever changed.  You have 2 different types of taco shells, brought together by a beautiful bean dip spread... How could you not fall in love?  Fast forward to a couple of years ago when they introduced the Doritos nacho shell... its good yes, but have you ever tried it on a double decker taco????  MIND BLOWING.  Ive never felt such happiness in my life (don't tell my 5 year old that) and now ill never know that feeling again.  Please bring back the double decker taco so I can continue to live my joyful life on cheat day.