i just came across the post and have read a good part of it. if my comments have already been covered i apologise.
I think that generality of training and specificity of training are two fundamental principles of training. Furthermore they are interconnected opposites like yin and yang:)
If they are actually inversely proportional then as we move from the beginning of the training period to the end of the competition period we also move from generality to specificity.
I also believe LT runs are part of the generality.
This pyramidal approach is in line with almost everything i have read since high school on training principles. It is also a Soviet style periodisation fundamental. It can be illustrated as a pyramid and the lowest level of that pyramid is general preparation. This is for establishing base levels and volumes for later training to be launched off. Enough time spent here is also excellent for creating longevity in careers.
Furthermore, Arthur Lydiard, whose way i also subscribe to, proposes large amounts of training done between easy sub max running and what seems to be threshold running. Massive amounts i should say. 100 miles per week is advised for 800-5000m. However, Snell the dual Olympic 800m champion, said he only reached 100 miles per week a couple of times per year. Mostly 70-80 miles per week was the average.
I have come to the conclusion that why I initially, and why people generally cannot accept Lydiard's proposal, stems from what i see as laziness. Now it is very difficult to propose that distance runners are lazy. So i will try to explain it like this. People will find it easier to do what is natural to them than what is not. A natural distance runner will want to do a lot of running. The lazier (must find a better word) MD runner will want to do a lot of race pace and faster stuff year round. This is like a sprinters mentality - less volume, more intensity. The less lazy MD runner will either know or accept the necessity to build up the deeper levels. The strange thing is that this training is actually easier. So it's not really a lazniess issue facing these certain MD runners. What is it? They don't want to do the stuff that they don't like. They say the don't like it because it boring. Why is it boring to them? Because they haven't found the mental state to appreciate it. The mental state of taking your time, that contains stillness, peace of mind. The maturer mind that comes with experience. Coaches need to counter this unwillingness of young athletes to persist with long running enough to start to enjoy the serenity of it. Running in beautiful places with friendly co-runners helps a lot.
If you are a runner - run, run, run. Be the person of olde who ran from place to place bearing communication. Let running become your thing.
Then apply intelligence to a process of preparation for a specific race distance. If Arthur Lydiard is any guide, once the deeper levels are well deveoped, plenty of time can be spent in the upper levels. The broader the bottom level of the pyramid, the longer and higher the peak of the uppermost level.
As you said Scuj - the fulcrum; where those life best performances can be performed.
Having said all of this - i am coaching a 15 year old 800m runner just 12 months in the sport. To date he has never done long running in his life except the occasional random one. His training was almost without aerobic content in the first year because he began training at the beginning of the season. I worked on his technical side, his mental side and his competitive skills side initially whilst trying to develop maximum speed and lactate tolerance eg 5x300/4min. There were two blocks of 6 weeks through this period where aerobic power was developed. eg session 8x400/1min.
Within 8 months he ran 154.8 which is the fastest state record in Australia. (there are no national records in u15 in Australia. He also ran 408.4 in the only 1500m that season and ran 51.79e for 400m. Again, he was not an athlete the previous season.
This last Winter for us in OZ saw him do more aerobic work (1,2,3 min reps off 1 min jog or walk for example) but still no regular long runs. He did however do a number of races and did seem to quickly hone his ability to run steadily.
In a few races so far this season he has cruised a couple of 408 1500s, a 155.1 800m off a 59 sec first lap and a 49.9 400m, also 50.2, 50.3 and a 48.7 relay split on a perfect night.
All of this is occurring without any LT training.
So i think LT training is a component like any other, bring it up to speed if it is lacking and maintain it if it is well ahead of other components. There are many other components.
general balance for the athlete, then specific balance for the intended event.