I study the YCF form with Gin Soon Chu, one of Yang Sau Cheungs 3 disciples, and I believe that this lineage has a strong argument for a great similarity with the YCF form. Great effort has been made to see to this.
As for the fa jin expression in this lineage, I am not aware of it, but perhaps that is because I have not been taught it yet. I have pushed with Chu Sifu and both his sons. While they again, may have been taking it easy on me, there was no expression of fa jin such as I felt when I briefly worked with Wang Hei Jun, the Chen stylist, recently.
The more one sweats in times of peace, the less one bleeds in times of war.