In The Eminence in Shadow episode 2, Cid is "training" with Claire and when Claire is about to slash him, he moves so fast that he's able to side-step, slash his sword 4 times, go back to his original position, and pretend that he got hit. After the fact, Claire acts as if nothing abnormal happened, as if Cid had never done anything, but she feels a small chill on her neck (where Cid almost slashed).
The human eye can't see things moving faster than 550 mph (which would be ~1.6 the speed of sound).
But is moving at Mach 2 speed enough to replicate what Cid did? Or would it have to be a whole other scale like the speed of light?
I'm looking more for a ballpark rather than an exact number, just so I can understand what is Cid's speed.
At what speed does he move? Sound? Light?
Other instances of his insane speed: