Guard crush may cause the next hit (normal, command, special or whatever) to hit meaty, making it less negative, making it positive, or making it have more frame advantage, and that´s why you can link "unusual" things after it. I don´t think there´more secret to it than that.
You can see examples of this in some of our vids like hitting meaty with Mature´s qcb+B or the last hit of Alice´s qcb+PP. In this way you can combo a sC after qcb+B with Mature or juggle with f+B after qcb+PP with Alice.