Game State Strategy: When to Bid Safe and When to Push
The Tight Bid (Playing with a Lead)
If you are winning, bid exactly what you have. Avoid "bags" that could lead to a -100 point penalty.
The Aggressive Bid (The Comeback)
If you are down, you need to "force" the action. Bidding an extra book to try and set the opponents is often worth the risk of going set yourself.