I'm sorry, but when did the thread start to include dragons? XD
It started when you started to question whenever a firebender could create a smaller version of walloffire that could be moved forwards, similar to what happened during Sozin's comet, but on a smaller scale.
I refuted that claim by explaining that something of at least that scale was performed without strain by a random circus firebender at night.(Not on Sozin's comet)
How is it at least that scale? It is bigger then this actual shield would be, and moved with as much ease as this shield would have.
How is it more then that scale? It is incredibly detailed, which must take a lot more power, and this was performed by a firebender that was barely even named, and almost forgotten about after a single episode.
A Master firebender should have relative ease to create a small wall of fire to be moved forward, similar to a wave.