I was watching someone a few weeks ago who looked fast. The young gentleman was fast enough that most of his training partners froze. But there was nothing smooth about his actions. It was fast, staccato, choppy. Then it hit me. Choppy looks fast.
Strobe lights tend to freeze people because each visual snapshot shows a discrete amount of motion without the "in between" and our brain fills in that the motion is unbelievably fast. But it isn't. No one moves faster under a strobe light. Everyone looks faster. You can simulate that by using jerky, choppy motions. If you do, not only are the motions not faster than being smooth, they aren't as powerful, either. The quick stops apply brakes to the technique.
Check me on this, but my impression (never really looked for it specifically) is that the jerky 'fast hands' stuff tends to be far more prevalent in non-contact stuff. Largely because non-contact is scored by what looked like impact. Real impact is different.
It does have some advantages. Discrete motions act as discrete observations in the OODA loop and you probably more easily get the OO bounce type of freeze. On that level, the appearance of speed may be better for fighting minds than actual speed. But it isn't nearly as good for fighting bodies. The other thing, maybe the big thing, is that it is okay if you are fighting other people's minds, but if you buy into the illusions, you may be fighting the threat's mind but on some level defeating your own. Coming to believe what in the end is only a trick. A useful trick, but...
Similar stuff with power. What we are conditioned to believe feels strong doesn't necessarily deliver power. From the time we were little kids and dad said, "Show me your muscles" and we flexed our bicep we have the idea drummed into us that strength is about size (big muscles) and rigidity (hard muscles) and static.
It gets compounded with the dynamics of social violence. Most of the conflict we have seen is social and almost all of the violence-- Monkey Dances. And Monkey Dances are about communication and messages. The message is 'look how big and strong I am' and so the person tends to square up (wrong base for power generation, all targets exposed) and turn red (turning pale is the survival response) and go up on the toes to look bigger (sacrificing from the base both balance and power) and to flex and tense all the muscles, looking bigger (and making actions slower and weaker).
We all know, and have been taught and trained that power comes from motion, that loose is quicker and hits harder than stiff, that structure doesn't require muscular rigidity... blah, blah, blah. We know this. But our conditioning says something else.
So we all have a tendency, when afraid or feeling challenged, to tense up. To look big. To concentrate on the illusions of strength instead of what we know about power. If the illusion over-rides reality, you will get generations of people trained to rigidity. You will even get people who can mouth the words (often in a fake Chinese accent) "Life is supple, the only rigidity is in death." Who then turn around and not only move rigidly but fail to think in their rigidity.
And they are completely blown away the first time they see someone demonstrate a ballistic strike. Or a body slam. Or even a good jab.
There is a saying that slow is smooth, smooth is fast. Sort of. But smooth can look slow, even when it is too fast to react to...and jerky will always look fast even if it is not. Relax. Smooth your motions down. If all you need are illusions, it doesn't matter. If you need the real thing, it may not look like you are conditioned to believe.