I\'m really feeling confused. From the docs at developer.android.com, it seems in order to keep my images scaled correctly (aspect ratio too) across all current Android dev
Yes. You should define different layout for different screen resolution.
When you are supposed to work with tablet kind of application. That time really you feel that. There is a need of different layout. Because Tablets always comes in different size.
One more thing, When you are working on android, means you should always taste your app with real device. And also test with different size emulators.