• Dantian: how to find where it is - conceptual and functional locations; what to cultivate in/with it. I think some of you were going to try bouncing your cell phone on your belly before you go to sleep (or get up) - I'd love to hear how it went! 
• Deep practice: practicing a small chunk of material repeatedly, focusing on feeling (not thinking, not judging) the difference between what's right and what's a mistake/deviation. This is what music/dance/language learners/teachers and top athletes and coaches have been using all along (perhaps to various degrees) to effectively and efficiently (i.e., quickly) improve or transform their performance and skill. Those interested in reading about real life examples of such methods can read Daniel Coyle's book The Talent Code, although my first recommendation (surpassing the book by a lot) is for everyone to simply do it -- pick one thing in your taiji forms that you'd like to *really* improve and try deep practicing it. If you need coaching on that, contact me. ;)
• Collective energy and collective consciousness: yes, these are real. Some can feel them, some can't; nonetheless everybody can recognize the impact if they pay attention. Various wisdom traditions such as Buddhism and Taoism (including Chinese Medicine) hold this to be true; in fact one could almost argue this is what inner cultivation necessarily leads to - a realization on the path if not the ultimate destiny. Modern sciences, quantum physics and neuroscience in particular - have been providing converging arguments and evidence as well. At a minimum this is the foundation of energetic healing modalities such as medical qigong and reiki. (Many book recommendations to come in future emails!) 

Living is a form of not being sure, not knowing what next or how. The moment you know how, you begin to die a little. The artist never entirely knows. We guess. We may be wrong, but we take leap after leap in the dark.
- AGNES DE MILLE