Here are my trading rules:

• Trade is good if our progress towards set completion advances.
Example: A A (before) -> A B (after)

• Trade is neutral if our progress towards set completion stays in-tact.
Example: A B (before) -> A C (after)

• Trade is bad if our progress towards set completion declines.
Example: A C (before) -> A A (after)

I do accept good and neutral trades. I do NOT accept bad trades.