I use a sawzall to cut the pelvis after the deer has been properly aged and skinned. I won't split the pelvis before I start to cut up the meat 'cause the hide pulles away and you wind up with some dry, wasted steak and roast meat. Plus the leggs stay together and don't flop around while the deer is being hauled out, stays much cleaner.
Just the way I was taught how and it works for me.