'Dominant Positions' in Practical Wing Chun

In class we've been looking a lot recently at 'dominant positions' - much like the equivalent of 'mount control' and 'back control' in Brazilian Jiu-Jitsu.

Rather than Wing Chun being about who can be quickest and get in the most hits, we want to lower the risk of getting hit ourselves, and get to certain positions where we are clearly dominant. From there we will then have an advantage over what happens next - regarding whether we want to hit or just control them. The most important of the '5 Practical Wing Chun Centrelines' for this is the 4th centreline - the contact point between our and our opponent's arms. In order for us to be in a dominant position, we want to have that contact point closer to our opponent than it is to us, whilst still retaining an elbow angle of 135° in our lead arm - as in the example below:

If we can achieve this, then it usually means that their arm has collapsed, and we have a strong arm structure that can then withstand force going into our stance. Not only is their upper body structure compromised, but so is their lower body, as ideally we want to make it hard at all times for them to find their centre of gravity ('5th centreline') and put power into their strikes. See if you can apply this principle in your own practice, and what effect it has on your opponent. Happy Training! - Sifu