Like anything else, prolonged imitative drill will certainly promote mechanical precision and habitual routine security. However, it is exactly this kind of "particular security" or "crutch" that limits and blocks the total growth of a martial artist. (Bruce Lee, Artist of Life, page 137)
This is a typical quote from Lee. He means 'mechanical' to mean a repeated rhythm, a routine rather than free-flowing action (or 'broken rhythm.) My use is in the sense of a physical reality, so when Lee writes..
However, we know, through instinctive body feel, that in any physical movement and for each individual there is always a most efficient and alive manner to accomplish the purpose of the performance, that is, with regard to proper leverage, balance in motion, economical and efficient use of motion and energy and so forth. (page 139)
.. that is also mechanical - so it's just a way of speaking.
Similarly, Lee says 'complementary actions' for fighting, while I often use 'oppositional'. Again, this is a way of speaking, and I tend to refer to feuding or low-level fighting (in communes or between men and women.)
Because we live in a system of variable time (machines, computers) I want to emphasise the mechanics of motion in invariable time. Obviously, this is what Lee did; words are just words, the understanding is what counts (thought, spirit, psyche, honesty.)