It struck me tonight when teaching my class how deep the various layers of taiji go.
Students by clumsily going throught he form and applications and then move through layers of detail until they eventually start to internally manifest jins within their body. This is when supernatural looking power can be achieved when paired up with other people.
Then the energy field is manipulated so that you can read the subtle changes in brain wave frequency when fighting with somebody or indeed treating somebody.
There are other stages in between but the latest stages involves moving back through the process of creation within our body. This is what is referred to when they talk about Wuji, Taiji, Yin Yang, Wu Xing, Bagua as a process of development.
This is the energetic shift from Congenital to Acquired as our body reflects the shifts of the cosmos in nature.
Taiji allows us to reverse this process and take our Qi back through the above levels until Wuji is achieved in the mind and the centre point of the Dan Tiens.
This is what they mean when they talk about Taiji as moving meditation. They are meaning that Taiji reflects the process of Internal Alchemy but this take s along time to understand.