I'm definitely missing something - as this technet article mentions installing only once... it's popping for every single 'print'.
Rsclientprint Dll
SQL Server Sign in. United States (English). RSClientPrint Download May 19, 2006. I have an asp.net application which is launched from our B2B site. The primary purpose of the application is to allow our external clients access to reports, along with the ability to export and print. The RS2005 report viewer component was used within the application to render the reports.
http://technet.microsoft.com/en-us/library/dd283109(v=sql.105).aspx
Using Client-Side Printing
Rsclientprint Activex Download
To use the print feature, click the Printer icon on the report toolbar. On first use, this will download to your computer a Microsoft ActiveX control that provides thePrint dialog box. Depending on browser settings, the control may be installed automatically, or only when a user agrees to install it. After the control is downloaded, the Print dialog box displays whenever you click the Printer icon so that you can specify options and send the report to the default printer. For more information, see How to: Print a Report (Report Builder 3.0 and SSRS).