I always cut or saw the pelvis. On a younger deer you can take the tip of your knife and use your hand like a hammer and drive it into the small joint between the bone plates and split it open. But on a bigger deer I carry a small Granfors Bruks mini hatchet in my belt pack and it makes quick work of that job.
Pulling all that back through the pelvis never worked for me and
almost always resulted in contaminating the meat with feces or urine as the tissues almost always tore open.
I also think cracking the pelvis open make it easier to get into the rest of the deer and helps with cooling the thing down.
“Est Nulla Via Invia Virute”