Others may have more expertise in the area of hollow built rods, but I'll share what I have gleaned from this and other sites...

Hollow built rods are lighter do to less material. As a result they accelerate faster than the same rod as a solid built.
Since bending stresses are mostly carried along the outside of the rod the strength is not greatly effected. Most hollow built rods are still solid in the tip section, since a minimim wall section must be maintaned for strength.

Back when bamboo was the only/best material available they also made 'double built' rods for extra strength. These were built of multiple layers of bamboo, kind of like a hollow built wrapped around a solid rod. I believe these were common back in the days that commercial tuna fishing was done with a rod.

I thjink they have made hollow built rods from the beginning, although curent adhesive and planning technology make them easier and stronger to produce today. Planning machines like the 'Morgan Handmill' make hollow building fairly easy.

The R.L. Winston company used to make hollow built rods with a fluted cross-section, cutting a U shaped hollow the length of the strip. This maximized the area of the glue surfaces and minimized the amount of material left in the center.