Quoted from gearheaddropping:
Oklahoma is one of the most brutal games ever made. I had a bet with a guy in our league that I could score higher by not touching the flipper buttons while he could try all he wanted to get points by using them. I won.
You are on to something: The more you analyze the playfields of various games, the more your realize how ingenious some of them are. Some are so difficult that you may never beat them, and conversely, some are so easy that they can be beaten routinely. Oklahoma, Slick Chick, Flying Chariots, Egg Head, Derby Day, Bank-a-Ball, Abracadabra, World Champ, to name a few, seem "brutal," but once you get the rhythm, and learn the key shots, they can be tamed. Granted, mine are home games set on free play, but playing them honestly, with the tilt still enabled and proper slope, etc., the occasional big game is SO rewarding. For me, I'd rather win one game in 8 tries on a "brutal" machine, than win every time on an easier one.
BTW-- Funny story: I was working on my River Boat and noticed that the 10's bell wasn't ringing, but was scoring. I was tweaking the gap on the relay, firing a ball, but no flipping, just to watch what was happening in the cabinet. Finally got the the gap correct, it was ringing properly, and I noticed that on my third ball of no flipping, I was already close to winning a free game. The fourth ball I played with flippers and scored 20 points. I shot the 5th ball, and went behind the cabinet game and won two games letting it do it's thing...