You know what? I am not going to disagree, but I am going to shift the conversation a little.
Let's say we replace words that exist now in the athletics lexicon with different words. Science-based or otherwise it could all sound different.
But if the basis of a training method results in high performance, then who cares really if we call it areobic capacity or not? We can call it that and it can mean one's ability to run at a high pace at a given effort and here is how to do it: ___________.
So, as long as we all (or a coach and athlete) agree that the intention for this period of time is to develop X, and here is how we go about it, then it's all good.
Some people don't even want to know that much.
There is the art and the practical application (later described by science) of coaching, Arthur was amazing at both.
I have Stefano Baldini's entire training schedule in fancy graphs, leading up to his Olympic gold medal marathon performance. It is simple and it is a lot like Lydiard. Rod Dixon ran a 2:08:59 marathon in NY pre super shoes, with leg cramps. His training was simple and it was Lydiard.
I suppose on a fast course, on a better day (was raining) an with supershoes he would have run 2:03-2:04...conjecture.
How do we explain Peter Snell's 1:44.10 on a grass track? No drugs, no super shoes, basically marathon training until the business end of the quality phase. Given that a rubber track is good for at least one second per lap, he would have in theory run 1:42.10. And...what about super spikes?? 1:41? Maybe? Let's talk about John Walker with the most sub-4 and sub-3:50 miles, very similar training.....there are literally thousands of other examples.
The language doesn't matter so much as long as you agree on any given day, a session was a session for stated purpose/outcome.
I do however think it would be good to get the science more commonly known as you say and settle on the language better (for accuracy) but what I do know is great performances stem from very similar training plans where 1. the athlete was injury free the whole time, 2. the aerobic foundation was set first, 3. the athlete got to train through an entire quality phase.
Answering another person's question:
Lydiard didn't have an athlete do 1000m repetitions during the base phase because it was all too common to go too fast, anaerobic (cannibalizing the mitochondria that were developed during that phase). He didn't have athletes do easier 1000s because they would be at 5000 or 10,000-like pace or perhaps even slower, so it is more effective to actually run that far or nearly that far at that effort rather than taking recovery or rest intervals. You get better aerobic development by steady state running done longer (during the base phase) than breaking up the efforts into 3 or 4 minute repetitions. The heart gets better stimulus from staying inflated for a longer period of time.
BTW, should anyone quote that Lydiard demanded X for Y length of time or else, is and isn't true.
I know many of the Lydiard trained athletes and the foundation of the plan was to get in approx., 100 miles per week, but he later changed that to X number of hours when an elderly lady told him that she was running 18 hours per week, to get in the 100 miles - ha ha.
But he applied what was most practical to the person at the time, considering the circumstances. I am coaching a former 31 minute guy who was trained by Arthur personally. Being a massive Lydiard fan, it is really cool when the athlete asks me a question, I answer and then he shows me old hand written notes from the man himself saying the exact same thing.
Understand the principles of his training and how it applies to physiology and you don't need to debate the language and until the business end of the training, the nuances are few. But you can take what looks like a Lydiard plan and f*ck it up. Good and bad training can look the same on paper.
Right here on the Let's Run boards, we are debating something that is 70 years old and there is a thread Lydiard vs Daniels that had someting like 500 pages to it.
At the end of the day he coached directly 17 Olympic gold medals before transitioning to coaching coaches. He was the national coach in five countries and was responsible for Finland's ressuragence. Knighted in two countries....I think time has faded his luster a little.
Now, if you want to quote igloi or something then that is fine, but we fully need context.
Peter Snell was to start another of his training cycles for international competition. He told Lydiard that he would instead start with the aerobic base building phase, he would do a two week speed phase, then get into the arduous base phase (they called it marathon training). Sound sacralige, but it wasn't. Snell being off for a while, wanted his form to come around, so that when he put in the near 100 miles, he ran well. It worked.
I have to laugh because I remember when Coe said that he ran 60 miles per week after winning in the Olympics, the whole western world went nuts and dropped the volume and upped the quality and performance went to hell.
About eight years ago, he came out and said that he had run 100 mile weeks in a base phase and done so in East Africa partly. It was during the racing season he was running 60 miles per week. Ha. CONTEXT.
What was a recent quote I just saw, 85% of Kipchoge's training is done in zone 1. So, we also know he rans 130 - 140 miles per week. Say what you want about his repetitions, but they cannot be fully anaerobic while running 130 to 140 miles per week.
Last comment: when concerned about repetitions or "staying in touch with speed" doing the Lydiard base triaining, athletes have a fartlek session done weekly. Additionally, strides that are alactic and over hilly environments if possible for some of the training. You can't tell me that that doesn't include some quality....(without straining).