I worked with 1st through 3rd graders and used a timer for reading fluency pretty much all of the time. Many of them seemed to have no grasp of the importance of speed. They would stop in the middle of a sentence, go back and start the sentence over, yawn in the middle of it, stop and make random comments, etc. It was frustrating because I was charting their progress and once they hit a certain target with their speed, and hit it 3 weeks in a row, they could be exited from the program. I didn't want to pressure them to "read as fast as you can" because that made some of them anxious and they actually slowed down. Personally I think "coding" is just a really dumb test. Too many kids who score brilliantly in everything else get average or low coding scores and it doesn't add up, or seem to mean much of anything about their actual intelligence (or what I would consider intelligence at any rate). I would buy into speed as a factor of intelligence in other sorts of tasks, but coding seems to depend way too much on other factors. Why not just have the person respond verbally, for instance hold up pictures of objects that they already know (like cat, dog, baby, etc), and time their response? Why is "motor speed" even a component of IQ? If it is, then people with disabilities like dyspraxia should have lower IQs as a general principle. All of the subtests should show roughly the same score (give or take), otherwise it seems like it's not really telling us much of anything about their overall ability.
Surprisingly, there is some relationship between motor speed and intelligence. Jensen is very hot on reaction time as a measure of "g". I don't think it's as good a measure (.51, the lowest on the WISC-IV, vs .83 for vocabulary, the highest) as, say verbal reasoning, but it has its value for many kids. Just not a good reflection of intelligence for some.
