Just recently read an article in Wired as to how the iPod was developed; one byline in particular caught my attention:
"Apple's designers spend 10 percent of their time doing traditional industrial design: coming up with ideas, drawing, making models, brainstorming, and they spend 90 percent of their time working with manufacturing, figuring out how to implement their ideas."
No argument could have been described more aptly as to relationship between solution architecture and development. That is, design is important, it is critical that it is conducted at the beginning, but in the end, it is in the implementation that real issues arise. It is the 'figuring' out how to deal with these issues and implement the design where the focus of architects and team leads should be.