Comment by philipalexander

Good article, though I think you should differentiate between types of 'walkthroughs.' I think the point is that you want the users to start using the application as quickly as possible without being hindered by a walkthrough. On the other hand it is important to teach users to use your application... and constraining yourself to commonly used functionality is dangerous. I find that it works very well to 'show' users by helping them do tasks right away (a walkthrough) instead of 'telling' them how to use the application and then leaving them to remember it (also a walkthrough).