If by trimming and shaping chicken for barbecue, you're talking about cutting the pockets of fat off thighs and trimming extra skin so that when it cooks it shrinks to the size of the thigh, I would recommend a small petty. That's what I use - a Sakai Takayuki 120 mm petty. Although I don't compete, I cook for practice to eventually compete; I'm an avid home barbecuer and KCBS CBJ.
I've never owned a honesuki, but certainly am interested in one, but since you're talking about lifting the skin to remove fat, but leaving the skin intact, you'll need a nimble, small knife to get into those places. A honesuki has a tall profile at the heel, midway, it still might be taller than a petty. So it may be hard to get under the skin without pulling it off, and then cutting out the pockets of fat. If this isn't what you're doing, and you're talking more about breaking chicken down into parts, then a honesuki could be exactly what you're looking for.
Personally, for barbecuing, specifically cutting fat off of briskets and pork butts and shaping ribs, I've felt that a very straight and short (height) blade about 270 would be perfect for these tasks, something like a straight sujihiki (but shorter) and almost like a salmon slicer, so you can really carefully cut the fat down to the right height so that when it cooks, it will leave the just the right amount of fat left on the finished product. This would also be a great knife to separate the flat from the point on briskets and to trim the fat between the point and flat (and all that weird, tripe looking fat there).
