Why would you train pure neijia? Because they are fascinating arts that I've been reading about for a long time, and the qualities you mention are attractive. I don't think no-wind up strikes are 'watered' down in non-neijia arts, they are just more powered by local muscle. One advantage of the neijia is that you can deliver significant power without having lots of muscle. But such strikes, done externally, certainly can work (and they are certainly easier to learn and use more quickly, two not insignificant advantages to the waijia). But if they are powered by local muscle (upper body muscle) rather than Dantien-controlled whole body power, all the time (check the requirements for taiji, bagua, xingyi movement), then they by definition aren't neijia. And one thing neijia masters say over and over is that if you want to get good at those arts, you have to go all in, re-training your body to move from the Dantien is hard, even harder if you're training it some of the time and training external arts some of the time.
Thanks for the response. I had wondered what you had meant, too.
But, dantien controlled whole body power all the time? Are we saying that's the end goal of the art? As you said, it's hard training to accomplish. If so, then Ueshiba's aikido would be considered neijia. So would Takeda's Daito ryu. As would Chen Fake's student Hong Jungshen and his students, Li Chugong and Liu Chengde. So, those lineages would be neijia if the actual training was handed down to all students. There was a reason for the title, "indoor disciple". Takeda stated only to train a few in the secrets. How do we, then, label those arts where only a few were trained in the secrets, which dantien-controlled whole body power was most likely one? Do we then say that neijia is only a term for certain people, rather than the overall art?