Hatha yoga is by far the most popular kind of yoga practiced outside India. It follows a straight regime of first practicing yoga-asana follow by yoga-pranayama before one goes into deep meditation. It is a sound practice. The logic is one has firstly to tame one's physical body (and in the process one's restless mind), than to tame one's breathing muscles (and in the process one's restless mind), and finally start doing deep meditation.
Putting aside other benefits arising from the practice of asana and pranayama, what exactly does a practitioner need to be trained to be able to do deep meditation? It may be difficult to achieve, but the theory behind is quite simple. Physically speaking one needs to train up oneself, so that one's abdominal focus (mind) can control one's pelvic floor muscles and diaphragm.
As one can appreciate, the hurdle of yoga is quite high. For most ordinary students, learning the asana is likely to consume all their training time. And most actually will be quite satisfied with the mind-body benefits derived from doing the asanas. The next stage, pranayama is not an easy hurdle either. For one thing, holding one's breath for any length of time will not be recommended for people with less than normal blood pressure or heart conditions, which unfortunately would be not too uncommon for middle aged people.
The practice of Taoist deep meditation is quite different. The practice has, in all history, been targeting to practitioners of the middle aged (or even middle-aged plus). Therefore its way of practice is more naturally fitted to such people. The theory and way of practice is considerably simply and natural when compared to those of yoga. The first step of Taoist meditation is to do the microcosmic circulation. Through this, one's pelvic floor muscles will be activated. The second step is, after doing many microcosmic circulations and when chi gets much stronger, after chi is circulated through the third-eye and down to the upper abdomen, the practitioner will stop driving up his sublimed sexual energy ("stop the fire: 收火") . He will then use the accumulated chi in the upper abdomen to activate the diaphragm. The third step is after the pelvic floor muscles and the diaphragm have been activated, one can focus on one's dantian and start doing deep meditation. The whole process is natural, and comfortable too!