Just about everybody wants to be more flexible. It’s healthy to be flexible, and having a greater range of motion can improve your quality of life (and having tight muscles can hurt). Being flexible is good.
Some people join Wushu or Taiji with the express purpose of “improving flexibility”. Kudos to you. Many of those students do make impressive gains in how close they can get their noses to their toeses. Others join for that reason, come not often enough, and then say, “You know, I’m thinking about joining a yoga class to improve my flexibility”. As a Chinese Martial Arts teacher, my response to that is “Yes, if you do go to a good yoga class multiple times a week, I’m sure your flexibility will improve.”
But, gosh darn it, if you came to your Wushu or Taiji class multiple times a week, and stretched for 2-5 minutes every day like we teach you to, your flexibility would improve just as well! (OK, OK, so sometimes I go over-time in Taiji class and don’t get around to my preferred 12 minutes of conditioning+stretching, but, still…!!!)
About Flexibility: flexibility takes time and work to achieve, and there are as many types of flexibility as there are muscles and joints in the body. You can be Gumby in one direction and still be C3PO in another.
For example: when dancers kick, they kick “high” – they turn their hips and do a vertical splits with the top foot well above the head. In Wushu (and Taiji), the key is to keep your hips flat and level to the ground during the kick, which means that Chinese martial artists don’t want to kick higher than their foreheads in practice – they don’t kick “high” so much as “to the head” (more useful, yes? :)) To achieve that, we in Wushu and Taiji use a slightly different set of stretches than dancers do.
Both types of flexibility are extremely impressive, though, and it’s not a big deal to switch from one to the other, so maybe that’s a bad example.
Here’s another example: we have a student who has extremely flexible hamstrings, but terribly stiff hips. Another has super supple hips for things like center splits, but the front of his hips are stiff like old toffee, so we spend time every week just stretching the front of his hips.
In conclusion, it is good to be flexible, and classes aimed specifically at improving your flexibility will do so if you attend regularly and practice frequently, but also be aware of all the different sets of muscles that need stretching and make sure to get a complete, whole-body stretch! In essence: come to class! (And remind me to switch from teaching/forms to conditioning+stretching if I threaten to go over-time in Taiji class again!)