There have been times when I could Fa jin (after about 2 years of practice) naturally while striking with fists or kicking. But after a few days the ability disappears again. It returns again after some consistent practice, but takes weeks and even months to return to the level that I gained insight about in the beginning. One thing I have learned is that Fa jin is not something that naturally emerges through practice, but it needs to be maintained through regular practice.
Any thoughts about it? Did anyone else also experience this stage in their martial career where they struggled to maintain the ability to Fa Jin?