Okay. I have been around this forum a while, and I have seen good basic information on how the VTEC works:
1. When you reach critical rpm, the VTEC solenoid is actuated. This opens up an oil passage, and
2. The oil pressure causes little rods to move, which lock up the 'high lift' cam followers, which formerly have been idling on the shaft containing all the cam followers.
3. The 'high lift' cam followers respond to the high lift cams on the camshaft, and override the other cam followers, resulting in the higher lift and longer duration which give increased performance above 6000 rpm.

Here is what I don't quite understand. Those little rods which lock up all 8 of the high lift cam followers must simultaneously go poking through holes in said cam followers, so that the changeover is smooth and complete in all cylinders essentially simultaneously. But everything is moving very fast, and I am trying to poke these little rods through fast-moving holes, and,.... Well, perhaps I am not articulating my concern very clearly, but how come the switchover never causes crunching and grinding inside of the engine?

It's all a mystery/miracle to me. How does it all get synchronized???

 

I'm uncertain of the oil pressure that is pushing on the pins, but I'm sure they push with enough force to quickly lock at the instant the holes are aligned. You also have to keep in mind that the rockers/cam followers are not moving at all times. They are only out of alignment when the cam lobe is pushing on the cam follower. The instant the valve is closed the rockers/followers are back in alignment until the cam lobe comes back around. They don't all lock at the same time due to some valves being open, but I'm sure the transition takes place in a split second.

I don't know this as fact, but it's my best guess. Here are a few pictures of the cam followers off a B16A2.