I must admit that for a long time I did not make the distinction between skill acquisition and motor learning. At first I thought is was just semantics, someone trying to create a new field. Over the past several years I have come to understand the distinction.
Skill acquisition recognizes the body as a complex system, not a computer to be programmed. The body is a self-organizing problem solving organism. Skill acquisition recognizes that there are multiple solutions to the same movement problem. One solution does not fit all. Essentially it is learning through exploration and discovery. Not about exploring limits, rather it is defining parameters. There are many learning options that allow for and encourage individual expression. Each person has distinct movement signatures; those help define us as individuals. I always felt that motor learning was trying to put us in a box, to limit us by limiting our ability to move and learn to certain strict rules.