Visual Studio reformats your HTML as it pleases when switching from design to HTML mode – a massive bug!.
(c) Mike Moore/Microsoft.
I found that the development team did seriously consider this bug. The first thought was to add an option to turn off the reformatting feature. Unfortunately, it turned out to be deeply integrated in the code that makes the editor useful. So, it could not be turned off. Nor could it easily be fixed. Any changes made to this area of the code would definitely impact many aspects of the editor.
Note to Microsoft’s VS.NET group – you blew it! Fix the bug, fix it before Whidbey!