I think what we have to consider as well is the act of teaching oneself the process of note recognition in an instantaneous fashion. The ability of which has to be honed repeatedly.
I was reading an article that described how a top of the mark virtuoso pianist can take multiple full segments of information on the page, can grasp this flow of information in mere seconds, and correlate that without hesitation and without delay, straight to the hands and ready for execution. With nothing more than a minor glance at the page.
Now, I can only surmise that having such ability would be at the stake of repetitively having to train yourself, memorize, watch the hands, feel the notes before they happen, know where on the keyboard you navigate to geographically and how this all coincides with your mental comprehension of the instrument while playing. I'm assuming all fluent and gifted artists of the trait can relate to all the senses required for play being able to feel coordination both physically and auditory. Being able to hear a certain pitch and coordinate the hands without thought to the appropriate place for a quick execution. It's like speaking a foreign language. You have to 'think' in that particular language per say to be able to speak it.
So I would hold the belief that going after every piece with meticulous diligence would in the end aid with the training of each and every sense that coincides with playing and how a person comes to understand how all the senses intertwine together. Even though this may be looked at as 'mechanical' I think that ultimately if a person is 'musical' then your musical. And you will make fit what it is you are trying to learn. Extremely slow practice at first sight will never be out right musical, because it's too slow. You can't sight read what you can't play. You have to know how it's played and envision it as its coming. As you initially see a piece for the first time, your basically collaborating this quote on quote 'new information' with what you have taught yourself so far.
Ideally when one is familiar enough with the piece, the expression and articulation start to arise. Like a musical epiphany stemming from areas of the piece becoming engraved in the mind, and then that's when the 'music' starts to happen. I would think that after having committed the time to have conquered this task on multiple occasions, across various rhythms, and enduring painstakingly slow but constant attempts, the process of recognition, of foresight and familiarity become second nature. And the main concentration is on the 'music' itself.
I may have potentially just answered my own questions. But I'm interested to hear what other people think. I've been playing now for about a year. Memorized a few pieces (can name if needed), all scales 2 octaves, working on arpeggios/contrary motion/similar motion for now. Although, I've only managed to memorize 4 Hannon exercises because Hannon makes me cringe with fear.