I only took a glance because .NET makes my eyes bleed, but this technique appears to be loading the external page into memory and then injecting it into his own page. The problem with this method is, all page loads will be done by the same IP address (the server) not the client. This will prob not work out well with zip submits, since I'm guessing they have some type of IP repeat filter. Especially when they get 1000 + submits from one IP address.