BIG BAD WOLF: "If I think I have a good chance to lose - deny the double"

Aye, that's a reasonable guideline to use at the start but you'll be at the mercy of those who know they can scare you by doubling. There are plenty of situations that look like you're going to lose when you should actually take. You'll know you're getting the hang of the cube when you confidently take what you would once have dropped.

Paradoxically a common feature in games with those who don't know how to judge the cube is for them to take a cube that should be dropped like a hot rivet. And when they get the 6-6, or whatever, and go on to win... Doh!