It comes down to the players skill with the character, not the characters stats. If somone is good enough with Tira or Siegfried then they will win. Sometimes fighting game communities focus too much on theoretical calculations and frame rates. Exploiting the system does not a good player make...
There is something to be said for not blaming your character for wins and losses. I see so many Tira players bitching about the patch. I'm a Tira player too, and if your skills are en pointe, you can find ways around all the "nerfs". So many people are playing the "I'm not playing anymore" trump...