Redefining Blocks made easy

I had a situation where a project drawing had some block definitions that needed an update.  The blocks represented mapping symbols such as a water valve, water meter, and so on.  They were defined at wrong size and on the wrong layer.  The CAD Standard requires these blocks to be defined as 1 unit across the longest dimension and all objects originally drawn on layer zero before becoming a block definition.  These blocks must also reside in the drawing template. 

 
To push the revised block definitions from the project drawing back into the drawing template appeared to be an impossible challenge.  Drag/Drop from Design Center was met with the usual “Duplicate blocks will be ignored.”  After wrestling with the dilema for a few moments I discovered Design Center (Ctrl+2) is still the right tool for the job.  You just need to use another option within Design Center.  Here’s how its done.

1. Open the project drawing. 
2. Open the drawing template. 
3. Open Design Center palette.
4. Choose the Open Drawings Tab. 
5. Right click on the block under the project drawing within Design Center.
6. Choose the Redefine Only command.

Problem solved.  Sorry, only one block at a time may be Redefined using this method.  Can you figure out how to redefine several blocks at the same time using block definitions within another drawing?