A successful bridge player will be a combination of these characteristics
In this pairs system, 3♦ showed 0-6 points, because otherwise they would have bid over 1♥ - they have the bid of 1♠ as artificial and to show 7+ points (not recommended).
At the table the player reasoned that partner could have 0 points and 3NT may have no chance. In practice, slight optimism here pays off. It's important to note that the opponents were not vulnerable and you are vulnerable - at such vulnerability often the opponents have very little for their bids and raises
Be practical and a little optimistic rather than pessimistic, especially when it comes to chasing those vulnerable games.
When the opponents are not vulnerable, they sometimes bid without having much at all - don't get discouraged.
The most important signals
Double or bid?
Bid as high as possible!
Defending against a multi 2♦
Transfer or not?
Nv compete
How strong vulnerable?
Preempt suit quality
6322 and 7222
2♣ opening
Doubleton lead
Passive lead
When to lead active
1N with 5422
Takeout double
Negative double
Splinters
Competing partscore
Try not double
Ace Ace King
2 level overcall
Lead Trumps #1
Lead Trumps #2
7 card GOOD suit
To open or not, pre-empt or not
Let the opponents play when they are misfitting
The strongest hand
Be practical