Time Turner was the best. Simply put, the best. He was the greatest Doctor anypony could ever remember. But like all actors, eventually, he had to give up the limelight and go back to the real world, with his marefriend, Derpy Hooves. So sit a spell, and learn about the colt's times and trials on the set of Canterlot's greatest series, Doctor Whooves.
Just a random idea I had. Pic credit goes to DiasFox of http://diasfox.deviantart.com. Please support their works.
Edit 22 Apr 2013: Here is a random alternate ending I thought of last night at work. I liked it too much to let it go unwritten, so enjoy.