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Wooh's Adventure with DSDM Principles - Practices

DSDM, or Dynamic Systems Development Method, is a subject not often associated with a children's story. At least not until now. Thanks to DevShed contributor Ivan Idris, we can all take a bit of a break while enjoying this tale about a very important bear and a very important subject. (Somewhat based on the books of A. A. Milne.) “Sometimes, when you are a Bear of Very Little Brain, and you Think of Things, you find sometimes that a Thing which seemed very Thingish inside you is quite different when it gets out into the open and has other people looking at it.” -- Winnie the Pooh, a totally different bear than the one in this story. Really.

TABLE OF CONTENTS:
  1. Pinnie the Wooh and DSDM
  2. Wooh's Adventure with DSDM Principles
  3. DSDM by Example
By: Ivan Idris
Rating: starstarstarstarstar / 23
January 26, 2004

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"The reason that DSDM is a very important subject is that without it important things would not be done on time or not the right way."

"Oh," then Wooh asked, to show that he was paying attention: "What are the DSDM principles?"

"Let’s use one of our adventures as an example of a DSDM project. Remember the time when you and Wiglet built a house for Ee-orr. Now you didn’t apply DSDM, but you still did a good job and Ee-orr was very pleased with his new house."

Christopher Robison picked up a stick and started writing in the sand. "This is the first principle." He wrote down with big letters:

ACTIVE USER INVOLVEMENT IS IMPERATIVE.

"The user in this case was Ee-orr and he wasn’t involved in any way, was he, Wooh?"

"No he wasn’t. He thought that his house was blown away by the wind and had landed where we built his new house with sticks. He was really proud of it, you know."

"You built a house just the way Ee-orr wanted it and you actually made an improvement by building it out of the wind. Normally you wouldn’t have that knowledge beforehand and you will really have to apply the first DSDM principle. The next principle is:

"DSDM TEAMS MUST BE EMPOWERED TO MAKE DECISIONS.

"Wooh, you made the important decision to build Ee-orr’s house out of the wind with sticks. Wiglet helped by suggesting using a pile of sticks on the other side of the forest. Clearly you were both able to make decisions fast, and that sped up the project."

"Wiglet and I were standing out of the wind when I thought of building a house for Ee-orr. We called the place Wooh Corner and we decided to build the house there. We could have called it 'Wooh and Wiglet Corner,' but 'Wooh Corner' sounds better, which it does and it really is one."

THE FOCUS IS ON FREQUENT DELIVERY OF PRODUCTS.

Wooh looked admiringly at the letters.

"Obviously this doesn’t apply, since you built the house only once. However if you were a company that builds houses from sticks – this principle would be very important."

"If the wind blew the house every day, then we would have to build it every day. Is that what this Princthingy is, Christopher Robison?"

"Not exactly, because you will then deliver the same product every time. I don’t think that you will do that anyway."

FITNESS FOR BUSINESS PURPOSE IS THE ESSENTIAL CRITERION FOR ACCEPTANCE OF DELIVERABLES.

"The business purpose here is providing a comfortable home for Ee-orr. You succeeded in that perfectly. Ee-orr however didn’t accept anything, since he didn’t know that you built a house for him."

ITERATIVE AND INCREMENTAL DEVELOPMENT IS NECESSARY TO CONVERGE ON AN ACCURATE BUSINESS SOLUTION.

"The first iteration was when Ee-orr built his house. He didn’t choose the right location and his house was blown away by the wind. Then, Wooh, in the second iteration you improved on Ee-orr’s design by choosing a sheltered location. Usually more iterations are necessary, but you were lucky to reach your goal in one iteration."

"That’s because Wiglet helped, and I guess I am a Very Lucky Bear."

"Yes, you are, Wooh."

ALL CHANGES DURING DEVELOPMENT ARE REVERSIBLE.

"Rev-esi-ble. What does that mean, Christopher Robison?"

"Reversible means that you can undo it. In this case you could have changed your decision about the location of the new house and placed it where Ee-orr originally built his house. The main advantage of this principle is that you can undo bad decisions and will not have to start all over again."

Christopher Robison produced a piece of paper from his pocket. "I have already written down the other principles," he said, and started reading quickly.

REQUIREMENTS ARE BASELINED AT A HIGH LEVEL.

"This way the final system is most likely to meet the users requirements."

TESTING IS INTEGRATED THROUGHOUT THE LIFECYCLE.

"The risk that the computer system will work incorrectly will be reduced."

A COLLABORATIVE AND CO-OPERATIVE APPROACH BETWEEN ALL STAKEHOLDERS IS ESSENTIAL.

"The implementation will go smoothly, because all parties are involved."



 
 
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