Common Design and Standards
It is as if evotards have never designed nor built anything in their lives. Why is that, you say? Well for one just being involved in building a house you will see bulding standards at work. The studs of a wall will be 16" apart on center- building code/ standard.
Floor joists? The same OR 12" apart on center depending on the load the floor will carry. (yes some can be 24" apart, again depending on the floor's load- I have never seen that spacing).
IEEE? Standards that allow for different companys'equipment to work together.
What does this have to do with a common design? EVERYTHING.
The point being is a common design is one that uses the same standards to construct something. That is the same standards others used to construct something else.
Other examples would be plug-n-play electronics, PC clones, rail-road tracks, roads, bridges, etc. (Russia used a different standard for their rail road tracks forcing Germany to refit their rail road cars to ride on Russia's tracks- WWII)
How does this relate to Intelligent Design? Living organisms were designed to the same or very similar standard. It does not require only one designer. Just one set of design standards that must be followed.