Because, as with many things, visualization helps.
So it seems that it's the term ki that you object to. Replacing the word ki with visualization doesn't alter the procedure, which in this case, is coordinating mind and body in order to improve performance of a certain task. And that's what ki is, a unified mind and body, no woo woo mysterious energy source, but a synergy that amplifies one's power in a way that can't be achieved by mechanics alone.
If coordination of mind and body strikes you as a little to Ki Aikido-y try Dan's definition again which is pretty non-denominational: "controlled use of the body systems through intent".