This is actually basically the same tactics used by Sun Zhu. The main difference is Sun Zhu had part of his army break off for the capital, the opposing army chased, and then was encircled when Sun Zhu’s front (the side heading to the capital) and back (the side lagging behind) turned and faced the opposing army.
The capital was never the main focus. Sun Zhu just wanted to move the point of engagement to an advantageous point.