The e-mail(s) is a resource that provides invaluable insight into the "Longhorn" development process; Allchin mentions an ambiguous plan (b) pertaining to the "Longhorn" storage subsystem, WinFS, and expresses frustration because of the operating system's poor performance. In 2006, Allchin said that when he wrote the letter he was being "purposefully dramatic in order to drive home a point," and acknowledged the positive changes that Microsoft had made with its development philosophy as a result of the development reset of Windows "Longhorn."