Importance of Duration and Landing task
F5B is known for its high-speed flying of distance task, but the competition is won by the combined total of three tasks (distance, duration, and landing) so don't take these other two tasks lightly.
Compared to the distance task, the duration task is relatively easy to score maximum points. Almost everyone scores within a few points of the maximum 600 points and also gets landing bonus points.

If you make mistakes in Duration or Landing tasks, it is almost impossible to make up for it with Distance task points.
The most common mistake is setting the power too high for distance task and running out of battery during the duration.
The most difference you get in the distance task is two to three laps. This is only 20 to 30 points but if you land two to three minutes early it will cost you 120 to 180 points. Don't take the risk and make sure you score full points in these tasks.
Practice the landing approach more so that you score landing bonus points. It is the same value as three more laps in the distance task.

How to calculate each task points.

1, 10 points for each legs in distance task.
2. One point for each second in duration task.
3. There are bonus points for landing accuracy. 30,20and 10 points for landing within the 10m,20m and 30m diameter circle.
4. There will be a one point penalty for each second you use motor for climbing (Round it down after the decimal point).
5. There will be a one point penalty for each second you go over or land earlier than 10 minutes (600 seconds).

Example

45 legs in distance task, 10 minutes 2 seconds in duration task and motor run time was 3.9 seconds, landing was 3 meter from center.

Distance task point    45x10=450 points

Duration task         600- 2= 598 points

Motor run                      -3 points

Landing bonus                 30 points

Total                        1075 points  

Because the round-down below the decimal point when stopping it at 3.9 seconds it will only count as 3 seconds.

When you think you will need to use motor, it is better to turn on the motor while there is still enough height.
Condition is always better at higher altitude and it is better to have enough height than marginal height at the end.

If your height is marginal and gambles not to use motor, you might stall it by trying to extend glide by pulling too much elevator or ended up using motor at very last moment and mess up landing pattern. I have seen many mistakes are made this way.

Do not hesitate to turn on the motor early. It’s only takes one or two seconds to go up enough height to complete the task,
in other ward it’s only cost you one or two points.  With enough height you can plan more accurate approach for landing.

Also do not go too high
Your model can get too difficult to see and it is almost impossible to tell when you are in good lift (unless it is very strong)

Mistake in power setting will cost you hundreds points by landing early.

Mistake in landing will cost you up to 30 points.

Using motor power during the duration task only cost you a few points.

Don’t  gamble, turn on the motor.

The most important point in practicing landing is not to take any chance.

If your approach pattern is as you planned, then continue to aim landing spot.

But if it’s too high or too fast give up the landing spot and land safely even if it is far out.

Most crush occurred during landing approach.

You won’t be able to practice any more if you crush your glider.

(Normal mode is 20% faster in speed than duration mode in my setting)

Gradually start adjusts altitude by flying big circle in upwind side which takes 30 to 40 seconds to make one complete turn.

You should have decided height and speed in one minute remaining point.

Glider should pass in front of you at 60 to 70 meter high in downwind flight at 30 seconds remaining.

Turn base leg after 10 seconds in downwind leg, spends 5 to 6 seconds in turning to final when if it is in almost no wind situation.

Make glide slope to the outer landing circle line by using crow brake. Be cautious not to raise nose of the glider. It will balloon and stall. Always keep the nose slightly down in final.

In case of strong wind condition flying 5 seconds in downwind might needs 20 seconds to come back.  Only practice makes perfect landing.

You need to discuss with your assistant about decision to continue to make one more lap or to turn on the motor to climb in last part of the 200 seconds duration task.

At the last turn.

If remaining time is 4 seconds, turn on the motor to climb.
If remaining time is 6 seconds, make quick turn and dive for the finish line.
If remaining time is 5 seconds, I will leave it up to you.

The important thing is to turn on the motor immediately when it’s became obvious it will not going to make the other base line and to put it in the climb at once
I have seen many mistakes by continue to fly to the other gate until buzzer sounds.

Zero seconds motor run in duration task are often seen as a high ranking player because they have better judgment to go or not to go and use last few seconds of distance task to climb without penalty.