I think the too-short barb means a hose that can't be double clamped. So it's excluded from the "if it can be, do it" recommendation. I generally agree that if the barb is long enough, it's a good idea to double clamp, particularly on any hose below the water line or any hose that operates under pressure. Above water line drain hoses are much less of a concern.
True, but the statement "every hose on a boat should be double clamped" might suggest a total lack of understanding why hoses either need to be or don't need to be double clamped.
I would venture to say if the USCG and ABYC agree that all don't need to be, then a statement like that is just parroting the dock talk/magazine article scribble, not the experts.
Thus why every inexperienced forum reader should investigate thread answers well beyond what they read here.
Heck, is that discussing raw water, fuel, coolant, fresh water, sanitation, sink drain, washdown, propane, icemaker, bilge pump, shower sump, dry bilge system, hydronic, air conditioning cooling and pan drains, icebox drains, wet locker drains, etc...etc...below the waterline, below the main deck, below the fly bridge??????
