I've never heard the term
spatchcock but that's something I've often done. I remove the neck bone, crack the breast bone so the chicken will flatten easier, remove the wing tips, and sometimes stick a narrow knife in the wing and leg bone joints and loosen them up a bit so that they're easier to separate after cooking is complete. I almost always remove part of the rib bones particularly the smaller ones, using kitchen shears.
I've sometimes thought of this as a whole chicken cut up but leaving just enough of the connections that all the pieces are still flying in formation.
I like doing this to a chicken because a flat chicken seems easier to cook than a whole chicken, whether grilling, or roasting or braising in the oven.