My exposure to Chen Taiji was limited, only a few years on and off and it was because I was adding some things to my aresenal and the Taiji sifu was a friend of a friend and wanted some of his guys to get some "real world" application for their taiji.
The push hands I was exposed to was very much "clinch wrestling" but because of the limited scope they were accustomed too it was very easy, in the beginning, to take them out of their comfort zone and that highly specific "sensitvity" fell through.
Of course, with a few minor changes ( and a couple of major ones), they were able to adapt very well.
That is the case with the vast majority of "sensitivity training" like push hands and sticky hands.
Psalms 144:1
Praise be my Lord my Rock,
He trains my hands for war, my fingers for battle !