Hmm, good idea but it doesn't really seem cannon. You really think you would be able to repel combustion shots back. In the series you don't see Korra or Zuko bending back combustion shots
"Combustionbending is a form of telekinetic firebending.
[23] It consists of the ability to channel chi through the forehead, often marked by an intricate third-eye tattoo, superheating the surrounding air and producing a beam of explosive energy capable of immense damage, both in short and long range. Unlike conventional
firebending, which produces a flame from the body, the technique instead creates a powerful beam that explodes upon contact with a solid surface.
[24] Combustionbending can instantaneously evaporate large bodies of water and counter fire attacks, as demonstrated by
Combustion Man when he stopped
Zuko's fire shield during a brief altercation at the
Western Air Temple.
[25] P'Li has also demonstrated that it is possible to curve the beams." - Avatar Wiki