I have. In myself- how it shifts from day to day- and in others. When I sense resistance, it is a cue to me that I need to look more closely at what is really going on.
When one perceives a lack of control within himself, his response is to lock in. The muscles tighten, the breath shallows, and the mind closes. There are limited options if any. Paradoxically, this is the very moment when it would benefit to be open, examine the fear rather than identify and react, ask questions, and from it identify the desire, let go and be willing to change. His world, then, can be redefined into infinite possibilities.
This practice in catching moments of resistance and harnessing those opportunities to make qualitative change is the Yoga of Awareness leading to a rich, well-lived life.