Gotcha, I have a Shakespeare 12 ft rod that I swear is made of fiberglass, or at least a significant portion of it,so I think I get it with the weight part.
Taper and pattern determine the action/ speed of the rod, and weight or ease of use of the rod would be more determined by the material it is made with.
In theory then, with a really light weight fast rod you could be able to work longer than a comparable taper/pattern rod from, say, glass then.