#9 at Whirlwind (New Gary Panks S of Phoenix, a longish par 4, works pretty well. Right side tee shot can be shorter and is safer but leaves a longer second shot; left side is a longer tee shot and must carry some bad stuff and a bunker to the fairway but leaves both a better angle and a shorter second.
Agree with DB3 re Talking Stick #12. No point in going left there. That seems to be the problem with other split holes I've seen--the penalty isn't worth the gamble, a/k/a the reward isn't worth the risk.
BillV Castle Pines #2 is not split; #3 is as you say (a barranca in the middle), and I think works pretty well--the pros have used both sides, often depending on pin position. I don't recall the split fairways on CC of Castle Pines.