[QUOTE=YouKnowWho;1084934]I know exactly what you are talking about. You move in with lighting striking speed and hit on your opponent’s face 6 or 7 times before he even has chance to raise his arms to block it. When you apply this strategy, you don’t care about “bridge” but to enter through your opponent’s opening and run him down like a tank. This approach made me to fall in love with the mantis system in the first place.[/QUOTE]
That is one way.
But there is also speed in transition. Speed in leading the opponent’s intent.
It only looks like physical speed.
Japanese sword writings would say it is a mental opening.
[QUOTE=YouKnowWho;1084934]Unfortunately, we will need a dependable strategy when we get old, speed should not be the only thing that we have to depend on. If speed is everything then when we get old (lost our speed), any young 20 years old can beat us up. That will be very sad indeed. I agree that in the striking range, the speed is important. In the clinching range, the speed is not that important any more. The know how become more important. This is why when we get old, we want to get as close to our opponent as possible before we get knock out. 
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Wisdom and laziness can be good complements to speed 
Once you are in contact, it isn’t the speed to close in. But it is still the speed and relaxation in the transitions. I’ve seen this in the videos you’ve posted.
You still rely on mind speed.
[QUOTE=YouKnowWho;1084934]If you can wrap your opponent’s arms (like an octopus wraps around prey) and temporary disable his striking ability, the speed won’t matter any more, you can then consume him slowly after that. 
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Sounds like a plug for BJJ 
We still prefer not to have protracted contact. We still can use body to body striking. Two of us classmates liked to train short range body striking.
If you are that close, body strike and/or throw, and disengage. Even from outside range, close in, strike, body strike, takedown and/or disengage.
One classmate watched us train body striking. He asked to join in. My partner went first. He is lighter than me. I didn’t get my turn. When the classmate came back a week later, he showed us under his shirt. The entire right half of his upper torso was purple and yellow from the previous week.