Sorry if this is a stupid question, but it doesn't seem immediately obvious how a thin strip of paper tape actually helps the taping process in drywall installation except for perhaps reducing the amount of mud needed between panels.
This, from eHow:
Embedded in a layer of drywall joint compound, drywall tape creates a physical bond between adjacent sheets of drywall. Although the bond does not significantly contribute to the structural support of the drywall sheets, the bond reduces the movement and cracking of the sheets.
Wouldn't simply mudding between the joints have the same strength without the tape, albeit requiring more mud?