Here are the reasons why this is faster (if you're interested!):
- The download of the solution is quicker because of the smaller file.
- Only the core ribbon definition of the entities you need are downloaded. The core ribbon definitions are not contained within the solution it's self and must be downloaded by the RIbbon Workbench separately,so if you load a solution containing all entities in your system, you'll be waiting around needlessly.
- When publishing the Ribbon Workbench will re-download your solution to make sure it doesn't overwrite any changes that have been made to other customisations since you've loaded the solution (this is a common problem when manually editing the RibbonXml and when using other Ribbon Editing Tools). Using a smaller solution means this re-download process takes less time.
- The upload of the new solution is quicker because of the smaller file.