Sifu's baguazhang and tai chi features extensive use of 70/30 stance. One aspect of this is the use of angles. It is fascinating in demonstration to discover how the structural parameters of 70/30 enable the peng to extend easily beyond your own body, with destructive consequences for the attacker.
The use of angles is extremely subtle and not really evident until Sifu explains it as you might to a young child. Then it makes sense. Explanations aside, the effect is undeniable and extremely powerful.
For the defender, the application of 70/30 is mild in terms of effort but amazing in terms of effect.
Sifu always says that if it feels easy and works, then you may well be performing it correctly.