Start from the beginning: How do you knit?
When you're a beginner knitter, you knit slower than somebody who's been knitting for 40 years. That's just how it is. It doesn't matter what knitting style the knitter uses; they have some serious hours clocked.
How fast you knit is down to muscle memory and developing habits. At the time of writing this, I've been a knitter for 10 years. Of course, I have been curious and wanted to try several different knitting methods as a way of making more time to knit and knit faster but I can honestly say that none of them seem to be faster than the other. Let me explain:
If you've been knitting for a very long time, for example, you learn to knit when you were four and you are now fifty four, the chances of you picking up a new knitting method and learning how to do it quickly are slim. Your hands are working against you. Part of your brain is saying "no, we don't do it that way" and your hands are confused. This doesn't make it difficult to learn a new method but it does add another layer of complexity to what you're trying to do. Bear this in mind when attempting to learn a new way of knitting.
A new knitter however, might find that there is no muscle memory bias. How to knit at speed and develop muscle memory to do it really well and efficiently is much easier if you haven't learned any particular method. If you find that you are not stuck with a certain way of doing things you may find using a new knitting style faster. You may pick up continental knitting. You may pick up Portuguese knitting. You may find that you're rivalling Hazel Tindall for speed. All, or none of these things may happen.
Knitting is a skill and skills need to be worked on over time to see improvement.
What knitting method is best?
Many knitters in the west will find that they have at least learned one of these two methods:
English and continental style. They're the most common.
There are some knitters out there who do a mishmash of several styles because they're self taught. The point is, your knitting technique only matters if you're not working on it. The knitter is the one who is slow or fast. Don't blame the needles or the method. How much time have you actually spent practising? There's a saying here that goes "a bad workman blames his tools." What did your addi's ever do to you?
I don't believe to this day that there is any one knitting method that trumps all others. Every pair of human hands are unique to the individual. What feels natural for one knitter might feel alien to another. Find your own method that works for you and speed will come later. Think of speed as a side effect rather than the main goal.
Knit in the way that is comfortable. Work on better knit technique. Speed will come later.
Back when I was a teenager (it gets further away every day), I was a competitive swimmer. My coach was in his seventies and there wasn't anything he hadn't seen when it came to swimming. I hated how slow I was compared to the kids who had been competing at a much younger age and I'd feel so inferior when I'd lose to super speedy splashers because speed meant everything, or so it seemed. My coach wanted me to work on my technique before anything else. He would say "Technique first and speed will follow."
He was not wrong. I wanted to be fast. I wanted to be the fastest. I was under the impression that the fastest meant the very best. It didn't. What perfecting my technique could give me surpassed any other element of swimming. It's all well and good being quick at front crawl with poor technique but 25m will be the only race you can win. See where I'm going with this?
I grew faster. My mission was no longer to focus on speed at all costs. My training was all about technique and endurance and before I knew it, just reaching further, moving differently, changing how I used my hands to grab water and even how I tumble turned all seemed slow but they helped me utilise movements and redeploy my energy to where it was actually useful. Speed did come. I laid the groundwork for success by focusing on technique.
What's more important to you? Speed of knitting or enjoyment of knitting?
What's the most important thing though? Knitting fast or enjoying knitting? Ever heard the saying "Time flies when you're having fun"? Maybe that's true for knitting, too; the more you do it, the faster your fingers will fly.
We really need to slow down both figuratively and literally. Knitters are on social media demanding to know what the next fastest method is. The fastest method is whatever method you have perfected the technique of.