You can have an early takeback and
a looped backswing. In the modern game, most players have a higher takeback. They turn their shoulders and coil and take the racket head back high. The high takeback is what creates the appearance of the loop.
The best explanation I've seen on the boards came from TCF. He described teaching kids the high takeback, and then to drop the racket into the hit.
Old school players like Jimmy Connors and Chris Evert take the racket head back early, but they do so with a lower takeback than modern players.
Look at this video of Wawrinka. His coach talks about his early take back. Since Warinka has a high takeback on his backhand, it also has that loop appearance.
This video has a pretty good explanation of the high takeback.
If having someone tell you to "stalk" the ball helps you learn early preparation or a higher takeback, more power to you. Personally, when I hear the phrase stalk the ball, i don't visualize any of that. I personally would need more concrete descriptions, such as, "take the racket head back high" "turn your shoulders" "drop the racket into the hit" etc.