ISPKI
Welding/metallurgical engineer/Metalsmith
The plus to the three barb design (to me anyway) is that it is a much tighter fit,and you probably woudn't need clamps (I overkill things though).For the amount of times the hoses have to come off,I don't think it's a big deal.
Rock
Those barb fittings are intended not to use clamps at all, supposedly it actually causes the barbs to cut into the inner lining of the hose. Since alot of fuel hose actually has a very thing lining to help it stand up to chemicals, those small cuts can actually causes premature hose failure.
It looks like those are threaded into the cap which means he could change the fitting style very easily to a single bump designed to be used with fuel injection clamps.