At the moment when testing path flows in taiji or through push-hands i find if an opponent puts force onto my chest/shoulder/upper arm via push/grab etc. i can neutralize and send an opponents force down to the ground and then 'bounce' it back combined with an internal turning to off balance him (though at the moment i can't do it as much as i would like).
So how does it work? He grabs your upper body and you 'bounce' him using the lower body and the ground. Wouldn't that say that there is a good connection between the lower body and the upper body? How do you see it?
I find that the further down the arms someone grabs me the more difficult it is, this maybe simply a psychological block on my part.
Or a training deficit in the sense that the connection from lower body to upper body is not so good in some positions, so maybe you need to figure out how to train that connection, increase your power, increase the strength of your dantien, and so forth? I.e., maybe it's something that's not a "how to" but a "oh well, looks like I need to train specifically at whole-body connection" and whatever other body tricks/skills that will give me the ability to do what I want?