Either "subconscious" isn't actually a word, or it's a word that refers to non-conscious parts of your mind. Things you aren't actively aware of, but that still exist. Don't treat "the subconscious" like an entity, especially not one that's considered separate/independent from the rest of the mind.
That is unscientific. "Subconscious" applies to things like habits and things that make you feel a certain way without your conscious acknowledgement, like the feeling in an environment or, you know, all that social micro-weirdness. Those can be conscious too, though.
That's what subconscious means in its most accepted sense. "Thought" that isn't made known to you. The things you do "automatically". There's nothing wrong with using the word like that, except possibly the inability to do so without being tempted to use it in the less-accepted senses that Sands hates so much. I guess I could see that. "Your subconscious" is a risky term. At the very least, because you probably can't actually be sure of what you're saying. "Your subconscious mind will learn -" could be seen as unscientific, here. Perhaps stick to phrasing like "You'll learn to ____ automatically without even thinking about it over time" and such. Partly to appease Sands, and partly because he probably has a point we're not 100% getting.
Assuming that's what his last post was referring to anyways. If not.. Go about your business.