The WeiWuWei principle, often simply also called WuWei (Japanese Moshu-Toku) or 'the art of doing no-thing' is one of the most high standing concepts in the martial-arts and thus also in WingTsun. But also other disciplines know that phenomenon, then under the name of 'the Flow' or  'the Zone'. It is a state in which everything seems to go by itself and on a flawless way – the applier self is hereby actually only a watcher of the own reached accomplishments.
Basically true WT mastership is the manifestation of WuWei in all activities, be it during a fighting situation or within the routine of the daily life. The biggest opponent of WuWei is the human mind. The reason is that thoughts are coming and flying along all the time because our brains are programmed to think, to compare and to judge. Therefore it is surely not an easy task at all to escape from the pattern of constantly thinking. But there are usable 'portals'.
'Doing without thinking' is completely not standing for 'thoughtless deeds' quite the opposite is true. Everything what is done – or un-done – in the state of WuWei bears its own quality. It is very hard to put down in words but it is nevertheless experienceable with the right guiding. Right now there will be WeiWuWei exercise sessions only on extra weekend stages in the NWTO academy; mostly this will happen in combination with a SCD/CoreMunication intensive training.