Quiet mind is not just quiet; neither is it inactive, nor passive. It is centred, anchored ruthlessly in dantien, so that it can intend – move energy, clearly and effectively, by stretching wherever it needs to go. This is good tension (the correct use of the word). The only reason for bad tension would be if the mind stopped being quiet and the resulting anxiety caused you to tighten up in an effort to hold things together and get things done. This is actually quite a complex and difficult procedure, and could only possibly be learnt if placed at a very young age in an environment saturated in chronic anxiety. Sound familiar?