You have to understand the hows and whys of Okinawan kata development.
I don't advocate form based training. Forms for the sake of forms is empty and useles.
There are no secrets, there are no codes.
The techniques I refer to are very simple things like shoulder throws, chokes, and basic locks.
Drills, combos, bag work...all of those train technique as well, if not better than solo form practice.
One step sparring and the majority of kata style drills are an exercise in elementary school karate, literally. They are worthless, a waste of time.
The human race continues to fight in the same manner it has used since the dawn of time. All that's changed are various circumstances adn theories (usage or armor, difference between civil and military usage, etc). I really doubt that in Okinawa two hundred years ago that in order to fight, men drew up into horse stance and pulled both of their fists back to their hips.
Blocks? There's no such thing as blocks. That is an elementary school level of understanding of the kata.
The original Kanji for "block" is 受, pronounced "uke". This does not mean block. . These were techniques for receiving an opponent's motion and countering, usually with a throw or a lock.
Here is a static example for you of your example of the "low block".
Face your partner. With your right hand, grab the sleeve of his dobok at his right upper arm as you enter his right side. Step behind him, getting your center of gravity next to his. With your left arm, reach across to grab the left shoulder of his dobok (or possibly his hair, ear, or fish hook him). Now, let your left arm perform that low arcing motion.
In Enshin Karate, this is known as Ura Nage, or "back throw". It's not to be confused with Judo's ura nage, a sacrifice throw.
There is no such thing as chambering. There is however grabbing, entangling, and pulling an opponent's limbs.
Kata in Okinawan karate developed for a reason.
Koryu jujutsu was originally taught in two man kata, in a static, "dead" manner. The Koryu had scrolls (maki), that contained the syllabus, skills, and secrets of their individual schools.
Kano came along and changed all of this, and in Judo, throws were taught in an alive manner, leading to the general superiority of Judo over many Koryu schools as far as throws are concerned.
Continue the development, and we see the evolution of Brazilian jujutsu, one of the most modern and sophisticated martial arts taught today, enjoying amazing success.
Traditional Karate kata were one taught in two man form as well, with joint locks and throws being taught in a similar manner. However, there were no scrolls or written syllabus. Rather, there was the solo form, which served as a moving syllabus for a given teaching. This required having a teacher who could show you how to perform the techniques of the kata, as traditionally Okinawan karate was passed on from one teacher to one student.
No Judo came along for Karate. Rather, karate was "dumbed" down for elementary school students. Kata were taught as a sole means of development, rather than as a complete syllabus.
This karate is brought to Japan, and from Japan, to Korea. This is the post popular perception of kata...that they are a collection of block-punch, or block-kick techniques.
Overall, in today's age, I would say it is not necessary to have the kata.
However, if you followed the parallel historical overview, I would say the contents of the kata syllabus have not been studied in enough detail to develop them. Rather, they have been dumbed down.