[Christ]

The primary benefit to that is the reduction in 'crank throw' during the power stroke, mostly.

What happens is that the piston, during the power stroke in a zero offset engine, has to go through an arc of about 180 degrees [2 radians, which I'll be using herein because I'm studying calc/trig and need to use the terms - bare with me]. The more offset the crank has, the lower the ratio of radians per stroke length, which equates to an obviously lower 'arc profile' and creates more linear force over a shorter distance. The end result is that the power stroke occurs over a shorter period of crank travel [in radians] and thus equates to higher /leverage/ on the crank, increasing measured output.

Honda has actually used the design in a whole bunch of stuff ranging from two stroke dirt bikes to marine engines and now cars. They seem to be having success with it, and Honda machines tend to have some of the highest output available in motorsports [or so I've heard] so I'd guess that the longevity of the technology should be a testament to it's gimmick factor [or lack thereof].

At this point, I want to point out that I am BY NO MEANS an expert in the technology. I've read about it, even thought about doing something similar in a more make-shift approach [line-boring a D15 to accept a D16 crankshaft using an offset bore].

Another benefit is the use of a larger stroke-diameter crankshaft with shorter piston stroke, reducing bearing wear [longer travel per revolution on the bearing] and helping to combine benefits of shorter and longer stroke engines.