It's always kind of interesting when you have to explain and justify what seems like common sense. But like SOA, Enterprise Architecture seems to need constant justification and explanation. Why is that? Is it because we make what should be fairly straightforward concepts overly complicated? I tend to think so. Take a look at many of the EA frameworks available and your eyes will probably roll back in your head and you will lose consciousness.
I think keeping things simple tend to lead to more success. A major medical institution that will go unnamed spent millions of dollars on an automated medical scrubs dispensing system. It was going to save lots of money, folks wouldn't be allowed to take home and keep extra scrubs. After installing and testing the system, all things were go. Unfortunately there was one major flaw, a human being still had to load the machines each day with the clean scrubs.
As you might imagine, scrub machine loader is not the top end of the job spectrum. Scrubs are not one size fits all and each machine was responsible for dispensing the correct sizes. You can see this train wreck coming yes? After only a few months and tired of not ever being able to get the right size of scrubs, the employees figured out how to defeat the machines and keep out more scrubs than was suppose to be allocated. Millions spent and nothing gained.
When I was a young Army officer many years ago, I learned a very valuable lesson. Everyone needs to understand the mission. And by understanding it I mean be able to execute it. It seems like common sense doesn't it? If the leader becomes unable to perform his or her duties it falls to the next in line to carry out the mission.
In my simple world EA is also very simple. Define the destination, show everyone how to get there and then help them along the way to make sure they stay on course. Of course the downside to simplicity is that things don't tend to fail in such a grandiose way like when they are over engineered and over architected. Still it is important to realize that simplicity is not easy to achieve. Complex systems tend to form naturally.
Ultimately I think one of the keys to achieving simplicity is constant vigilance. How you get this working state of vigilance is the topic of another post. The hint is, there is not one answer for all.