I'd call this "Disk Management 101", in that it covers the basics. I'd say the majority of the people in this forum already have implementation plans for storage capacity planning. I was personally really hoping to see more about External Capacity... can we expect one of those in the future, too?
Given the above, SQL Profiler, and a good trace template, I have found it quite easy to point out Internal (SQL-object based) performance problems. But what about those problems not associated with I/O? Is it a Network Problem? Client problem? I have theories about the problems that I have encountered over the years (like if MS Access is running a query and the CPU is pegged, then leave me alone ), but what if it isn't Access? How do you work with your network team to find the problem?
I am a firm believer that network n0mes don't exist.