They are pretty simple to understand, the only one I'm confused on when to use is the Martial Arts skill. The main problem we run into is the small number of Hit Points you have. I realize that its part of the design, you have only a few HP so that your characters are fragile. The group I'm playing with is more into cinematic/pulpy combat, so it takes away their fun. Adding additional HP to the characters alleviates this, but then the game balance is off since the injuries don't have any impact so long as your health is greater than 0.
That's where the Savage Worlds type combat has some appeal to me. They have it built in that your wounds all incur penalties, so your characters still seem fragile. However, they also have the ability to pull off some crazy stunts without the concern that doing so will get them killed immediately after.
What Savage Worlds doesn't have, that I'll definitely miss, is a few of the investigative skills (such as Luck and Idea) that have been a huge help in getting all of the information across to the PC's.
The bottom line is that its not a problem with the CoC rules, its an issue with how we choose to play the game.
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