The concept of wider power boats has been discussed for years but it was always felt that narrow hulls were faster. This is certainly true of displacement hulls, where the vessel's form is continually fighting an uphill battle to climb over a bow wave that is the product of it's own passage. No matter how much power is installed, the boat continues to create a bigger hill to climb, made possible by the large quantities of power being transmitted into the water. A tugboat is the classic example of this battle of the laws of nature. Broad, deep, powerful, and of course heavy, tugs can never get out of their own wake.
Reduced weight allows a shallower, narrower hull requiring less power.
The rowing shell is the antithesis of the tug. Light to the point of fragile, extremely narrow to the point of unstable, long and shallow, it is easily driven by low horsepower. Climbing it's own waves would be no problem if it created any waves to climb. The marine industry, being as conservative as it is, took forever to get over this concept and to this day still struggles with it. Wide and narrow have their place in combination with other factors, but in the new runabouts wide is definitely the winning combination.