Sophisticated theoretical knowledge underlying teachings such as Buddhism, Taoism, Yoga, Zen, Chan is not required for realisation. Moreover, this can build up mountains of complicated thoughts, opinions and expectations. Keep away from over-thinking and remember that the essence of the deeper understanding lies in simplicity. Just breathe in and out, that's all you need to realise that the Buddha nature always is, has always been, and always will be, your own nature.