Well than my theory is unexplained then, because I originally bought a cheap cable going from my PS3 to my TV but since upgrading to what I thought would be a better HDMI cable going by my theory it runs faster - wasn't jittery as the cheap HDMI cable.
Could you please elaborate on what you mean by "wasn't jittery as the cheap HDMI cable"? How do you define "jitter" in your scenario? Maybe it means different things to different people.
My understand with the 100hz thing is that it's just a processing function that some LCD TVs do to any(?) signal they receive whether from HDMI, component, S-Video, composite, etc, and that it's not necessary for plasma TVs.