There is a enormous amount of modern commentary on taiji, either by, or demanded by, Westerners. From what I have read it attempts to demystify taiji and explain every aspect of it in reasonable terms – it turns this beautiful internal art into another external system of exercise. The basic difference between a person devoted to the Internal and one driven by the External is that the first impulse of the former is to give, unconditionally, whereas the first impulse of the latter is to take, or at least worry about what they will be receiving. The student of the internal gets out of bed in the morning because taiji (or whatever it is that they love) calls to their heart and draws them into another day of devotion. Ultimately I suspect that we are all devotees of the Internal, it's just that many of us forget that first impulse and get distracted or caught up by externals.