From my experience..... In the KF I practice we work on grinding arm as opposed to push hands. From the start we work on developing structure and grounding the incoming force, then on bring the force from the ground out though our hand. This is great for developing good root and also for developing listening skill... When grinding you need to feel whether the opponent in pushing towards you or away from you. You also get to feel if the other guy is pushing from the ground keeping the body neutral or whether they are leaning in (in which case you let go and they stumble)
When I went to my TCC teacher he showed me single hand PH drills. The first couple of guys i pushed with complained that I was being to strong, so I softened up a bit. The problem I found was that when i actually went through with a push the other guy continually stumbled, where as my structure remained stable when they attempted to get me in a similar way. When I pushed with my teacher I found that he was soft also but he had the structure there the whole time and there was no point that I could take advantage. My teacher explained to me that there needed to be structure behind the softness, often people push with the sole aim of being soft and neglect the need to defend themselves... I.E: they are hollow and easy to push through.
With the PHs group I have been going to the same thing arises. When I am pushing there is no structure behind the softness and the other guys are hollow and easy to dominate if I choose too (sometimes I do but often I choose not to)
So... I personally believe that developing the structure with minimal use of force is the first step. Often people are far to hard at this stage and need to relax. But not to the point of spaghetti..... what is that lovely TCC term... that is right... SUNG... Those I teach have a far more solid beginning, but this is from structure... not just being soft, over time this becomes softer. The point being there is no point being soft if there is no structure, with good structure the body can still be soft, appear hard to the other guy and still maintain the qualities of adhereing, listening and leading....
Anyhow just my thoughts....
... ohh and Klonk...
I think you had better interpret yielding as rotating, not just as withdrawing, or you will often find yourself out of distance to counter attack.
QFT