Immersion!

Whether it's with weapons, or empty-handed, the thing is this: we can't hang back. We can't be purely defensive. If it takes too long for us to catch the turning tide of their attack, to spot an opening, we will simply be overwhelmed. Tai chi is certainly counterattacking, but it isn't and can't be purely defensive. If our technique is good, perhaps we can cut down on the lag-time between attack and defense: ideally they are simultaneous. The weakness with many Pushing Hands drills is that they subconsciously train us to allow five, ten or twenty attacks to go without a decisive response. Repetition is key to making the movement a habit, but we don't want to make  a blind habit where something is applied in an inappropriate manner. The point of Five Element Arm, for example, is not to be able to deal with five punches, but to deal with changing and varied punches. But really, we don't want anyone to land two shots on us, or even a single one if possible. This doesn't mean however that in training we don't ever let anyone land anything on us...It's tricky stuff this. We need to train the swift response, and the seeking out of the gaps, and general non-compliancy. We also need to feel what it's like (to a certain degree) to take a bit of a pasting. But it's important to know which we are training, and to realise that neither has the monopoly on "realistic".

This brings me to something that I've been thinking about. The benefit of some random, non-compliant, free-response training is boundless, simply because of the non-linear nature of the martial arts. A picture being worth a thousand words, anything that approaches a "whole" or "total" situation will encourage learning in a way that broken-down, linear-organised drilling simply won't. The danger in the first case is that it's easy to confuse with "reality". Now, five of your training partners coming at you in an intense and unpredictable way is a good training tool, and nearer to the "total" picture than is, for example, Seven Stars Stepping drill. But it isn't "total". "Total" can only happen in those nasty real-life happenings outside (hopefully!) the dojo. No-one is going to confuse Seven Stars with a "real" situation.
When you throw new people (or even more experienced sorts) into the "free" situation (and there are still plenty of rules and provisos for sure...) they can flounder and panic. This is where the more limited drills come in: they give the person the courage to enter fully into the "free" situation. They may even enhance their skills when they are in there. But what they also do is to give a kind of "spotter's guide" as to what's happening there amidst the hurly-burly, so they can identify and learn. It's like giving someone on safari some binoculars and a book which identifies the relevant beasts, but the obvious wonder of the safari is in its immersive quality and not for example, in the exact total number of wildebeest spotted. We want to get people to the point where they can spot for themselves, because then the real learning appears rather than the copying, mimicking or following.