It does not vitiate your point, but for the record dead reckoning is not so simple.
In navigation, dead reckoning is the process of calculating one’s current position by using a previously determined position, or fix, by using estimations of speed and course over elapsed time.
I’m remembering that in the latter part of his sailing career Josh Slocum, a fellow Vineyarder at least some of the time, famously sailed around the world by dead reckoning.
Slocum navigated without a chronometer, instead relying on the traditional method of dead reckoning for longitude, which required only a cheap tin clock for approximate time, and noon-sun sights for latitude. On one long passage in the Pacific, Slocum also famously shot a lunar distance observation, decades after these observations had ceased to be commonly employed, which allowed him to check his longitude independently. However, Slocum’s primary method for finding longitude was still dead reckoning; he recorded only one lunar observation during the entire circumnavigation.
Polynesian navigation uses an an astonishing array of perceptual inputs. The book Hawaiki Rising by Sam Low (another Vineyarder as well as Hawaiian) discloses many of these in the course of telling how they’ve been recovered.
To the point, however, just how people learn and get better by practice is the question Patrick is interested in.
Bowling, tennis, ping-pong, darts, shuffleboard, bocci, croquet … endless examples. In curling teammates intervene ahead of the trajectory.
Practice strengthens memory as the basis of imagination. You may recall the demonstrations that basketball players improved in foul shots just by imagining successful shots. (Here’s a 1989 thesis investigation.) But by practice the execution becomes more consistent and reliable as intended. That’s where Patrick’s interest in motor control applies. Looks like both are needed.