Currently I have two projects that are separate from one another. The first is a VB.NET desktop application that is already pretty large and a probably a bit bloated. The other is an older ASP.NET project. I've been tasked with integrating the functionality of the ASP.NET project into the desktop application. I don't have a specification yet for how it should be done. We're still planning it/talking about it. But one of the biggest concerns that the team has is if the desktop application will take a performance hit by adding a significantly large new feature. I'm inclined to think that the .exe is just going to get a little bit bigger. But load times and such shouldn't get longer? 

The way I think it will be implemented is as a separate window that's functionally similar to the web application. This window would be accessed by pressing a button on the main menu bar. 

I know there's not much detail here, but should I expect the rest of the application to take a hit on performance by adding a large new feature?