Grammar books with explanations and exercises have been published by knowledgeable language specialists to make learning grammar easier so that learners don’t have to discover grammar rules anew the hard long way. A learner of English can’t rely on real life communication alone to be proficient in using grammatically correct English. Learning English grammar from books, audio and video aids is equally indispensable to substantially
accelerate mastering of English grammar.

Correct oral communication in English is based on knowledge of English phonetics, grammar, vocabulary, and on practice and experience in communicating with native English speakers in real life.

In my view English communicative integrated skills courses that practice listening, speaking, reading and writing alongside pronunciation, grammar and vocabulary are the most effective and the most comprehensive courses. Conventional communicative English teaching and learning supported with adequate regular long-term practice in listening
comprehension and speaking in English yield effective results. Lack of such practice in English by learners produces speculations that conventional English learning and teaching methods don’t work.

Knowledge of grammar rules reduces making mistakes by learners. Without adequate
knowledge of English grammar rules learners often cannot create their own grammatically correct sentences and often cannot understand what they read or hear in English exactly.

In my view learning English grammar in the following sequence ensures firm solid thorough knowledge of English grammar:
 
1. Read a short clear easily understandable explanation of a grammar rule.
2. Study several practical usage examples (sentences) illustrating that
particular grammar rule. Check yourself whether you have mastered the
examples.
3. Do several exercises for that rule with communicative content (with
sentences that most likely can be used in real life situations).
 
Grammar exercises that contain dialogues, interrogative and statement (or narrative) sentences on everyday topics, thematic texts and narrative stories are especially effective for mastering grammatical structures.

Grammar practice should also include exercises in listening comprehension and speaking, not just in reading and writing. Grammar exercises must help learners not only form correct sentences, but also use them correctly in context in real life situations. Contrastive and
contextualised exercises give practice in form, meaning and use.

It is very important to learners for practising English grammar on their own that there are answers provided to exercises in their grammar practice book for self-check. English usage reference books help people avoid making mistakes in English. In such books learners and other users of English can find answers to their questions about correct English usage. I believe the following English usage reference books are comprehensive and very helpful:

1. Longman Guide to English Usage.
2. Practical English Usage (Michael Swan).3. An A-Z of English Grammar & Usage (Grammar Reference) [Paperback]
3. Geoffrey N. Leech (Author), Benita Cruickshank (Author), Roz Ivanic (Author), 2001
4. The Cambridge Guide to English Usage.
5. Collins Cobuild English Usage.
6. Fowler’s Modern English Usage.

Languages are obviously controlled in the brain, but it happens at a near sub-conscious level, just like walking. I, too, often use driving as analogy (but in a different way). Just like walking, the physical ability to drive a car smoothly comes from lots of practice driving, not conscious knowledge of the rules of the road. The latter is obviously important, but one could know every word of the rulebook and not be able to drive worth a damn. The same is true for knowledge of grammar. As I saw in Japan, many Japanese native speakers (including English teachers) had memorized massive amounts of knowledge about English grammar, but were not able to apply it in speaking. This is the difference between declarative and procedural memory (you are promoting the former, while the latter is what really matters when it comes to acquiring a foreign language.) 

I disagree with those allegations. Are you saying that teaching languages is unnecessary and teachers of languages are not needed?
Your comparison of learning a foreign language to learning to walk is wrong, because learning a language is a mental process of developing language skills (not a physical process), and learning to walk is a physical process that involves developing a physical ability. I can draw a really valid comparison in this regard. Can you safely drive a vehicle on the road without knowing theoretical traffic rules? Will you learn traffic rules while driving on the road? So you must know theoretical traffic rules before practical driving on the road. Grammar rules can be compared to traffic rules; grammar rules have a similar role for learning and using a foreign language successfully and correctly to reduce mistakes and misunderstanding.
Without adequate knowledge of traffic rules a driver can easily cause an accident or can endanger traffic safety. Fortunately grammatical mistakes don’t have such potential serious consequences as traffic violations do.