The phrase "Good thing you know this strategy and you understood the twist" is correct, but it can be rephrased for clarity or emphasis. Here are a few alternatives:
1. "It's a good thing you are familiar with this strategy and have grasped the twist."
2. "Fortunately, you are aware of this strategy and have comprehended the twist."
3. "I'm glad you know this strategy and have caught on to the twist."
### Meaning
The sentence conveys relief or