Yeah, let's call it 'following'.
In my experience, when a truck does a crash stop (I had this happening to me while following about a second behind), you have the time to slam the brakes. Once that is done, you decelerate much quicker than the truck, so the one thing you HAVE to get done is move your right foot... so no fiddling with the mobile phone or nav unit etc. pp. when following. But this is no surprise.
In 'normal' situations, when the truck has to brake because of traffic buildup, lane swervers etc. pp., you even have to be careful not to over-brake and lose lots of fuel while re-accelerating :-)
Good point about nobody really caring for the 3-second-rule in heavy traffic. When I drive home about 3pm, traffic is mostly heavy in this part of germany. I usually look for a truck and follow. At this point, you have the guys on the left lane going by (about 10 km/h faster, if that much) almost bumper-to-bumper... even the stated 30 m are very, very rare to see. I'd say it is more like 10 m (30 feet)...
Considering this, I have to agree: you are much safer behind a truck at 30m distance than on the fast lane with half that or even less.
so long,
tinduck
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