The following article falls under the umbrella of "Physiology of Motor Learning"

sure the title sounds "sciency" but I'll try to make the point clear

I'm sure - well at least I hope - this will be the first of many articles (or excerpts) posted here.  Mainly to provide info., perhaps a different way of viewing things, all intended to be thought provoking and challenging to the baseball instruction "norm"

I'm not trying to get super-technical on everyone - just trying to make sense of all this stuff.

I will emphasize what I feel are the main points by underlining and italicizing key phrases/sentences

Here goes....

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From:

Hellebrandt, F. A. (1972). The physiology of motor learning. In R. N. Singer (Ed.), Readings in motor learning (pp. 397-409). Philadelphia, PA: Lea & Febiger.

"Practice does not make perfect. Only practice that yields feedback about the correctness of responses can generate advances towards perfection. If the activity content is largely irrelevant for competitive requirements and/or feedback is inadequate or non-existent, the practices will be wasted. There is no dispute that individuals without external correct coaching feedback do improve in performance but only to a certain level. Without instruction individuals tend to adopt expedient strategies for movement control, which quite often are not the best or most economical forms. This is why an individual can play golf for 40 years, never have a golf lesson, and struggle to break 90 for 18 holes. The expedient patterns that have been learned and perpetuated limit performance to that mediocre level.

For efficient and maximum performance ". . . the kinesthetic acuity we should strive for is not enhanced general body awareness, but rather, a more sharply defined and specific sensitivity to what is happening in those key maneuvers upon which the success or failure of complex movement patterns may depend" (p. 407).

Implication. The skill content of practices has to mimic that of competitive requirements if beneficial training time is to be experienced. It is wrong to practice something with good intent (e.g., "I hope it will benefit the performance") without being able to justify and demonstrate correlated transfer to a competitive skill. If this dictum is not adhered to then much practice will be wasted or even counter-productive. It is quite possible that movements practiced could be so irrelevant that their impact on hoped for competition-specific movements will be so destructive that performance will be worse than if no skill practice had been entertained.

The programming of appropriate transferable practice activities in an enriched milieu of correct instruction is a challenge for modern coaching."
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