You are probably referring to this KB article:
General Performance Improvements. When you create a stand-alone application you can also enable debugging. This will save the block diagrams so you can debug the application while it's running. Normally when you build an app the block diagrams is stripped.
The amount of impact that turning off debugging will have to your VI/app performance is hard to say. To
best way to get a VI/app to run faster is to improve the code in the first place. This means avoiding very large memory arrays, not initializing and closing references every time you iterate in a loop, minimizing file I/O, etc. If you provide some idea of what your code does, and can perhaps post your code, specific suggestions can be provided.
