"Direct" has a place in he universe.
Most flights out of SJC are "direct" flights somewhere.
That said, every single time, and I mean EVERY single time, there's a change of plane involved. I cannot believe that's involuntary, but rather, planning.
Also, as stories have shown, because of using different equipment, it's been possible to miss your "direct" connection if your inbound is late.
"Direct" is a fine thing. However, NW seems to broadly abuse it more than any other airline I've seen.
Steve