Just to be clear, you should never have any significant pressure on your knees in any of these stretches, let alone pain. Pain in your knees from stretching would be a very bad sign, whatever's doing that, stop immediately.
I also concede that you guys may know more about stretching for flexibility than I do. My knowledge is mostly anicdotal, from my own experience, and what I was taught in TKD. That said, it's hard to imagine someone going from inflexible to being able to do the full splits without some pain while stretching out those tendons.
I'd certainly be anxious to hear from anyone who developed a completely flat full splits who did not endure pain and discomfort while getting there.
Also when I said pain I was really meaning significant discomfort. Real pain indicates possible injury, back off. But all the same, getting into full splits isn't going to be leisurely stretching. At least not in my experience. I could be wrong
I also concede that you guys may know more about stretching for flexibility than I do. My knowledge is mostly anicdotal, from my own experience, and what I was taught in TKD. That said, it's hard to imagine someone going from inflexible to being able to do the full splits without some pain while stretching out those tendons.
I'd certainly be anxious to hear from anyone who developed a completely flat full splits who did not endure pain and discomfort while getting there.
Also when I said pain I was really meaning significant discomfort. Real pain indicates possible injury, back off. But all the same, getting into full splits isn't going to be leisurely stretching. At least not in my experience. I could be wrong