Hi, I’m Dan Chartier, I work on the Web Tools designer and helped improve its performance in Visual Studio 2010. For some background, Visual Studio 2008 completely replaced the original trident (Internet Explorer) designer with the FrontPage designer (which is also used by Expression Web). While we gained many improvements with this change, we received customer complaints about various performance problems that we wanted to address in 2010. In general, the designer is quite fast. This is especially true when editing pure HTML documents, which is what it was originally designed to do well. However, the designer edits more than HTML. It also has the rather sophisticated ability to edit ASP.Net pages containing various interesting web controls…(read more)