Hi Alex,
You bring up a good point, and I agree. I think alot of what is 'written', was just that, and not necessarily practiced, or self experienced by the one doing the writing. Below and behind can be the same thing... It is interesting though, just how much the lower dan tien is placed 'vertically' below, in older written info, and, in old taoist charts, etc...
If I think in terms of today, I can see how much information is passed on , from teacher to student, as just information, and not necessarily experiential, self discovered, or self experienced. Just information passed on. The areas of focus or accomplishment, by someone practicing, say qigong, can be quite diverse, and not necessarily focused in self inquirey, or meditation.
I don't think there are very many masters at Master Lin's level of meditation practice. Not to say they aren't a number of masters who have great accomplishments and abilities in healing and martial areas.
I heard him say, why he placed the lower dan tien 'behind' the navel. It was in meditation, and he asked his teacher/teachers(as in the master's energy), where it was. His master , with his finger, pointed/pushed in at his navel. I don't recall if he specified it was Buddha, or Quan Yin, Jesus...who showed him, in his meditation. It sounded like a group, and perhaps one stepped forward...
love,
gallen