Maybe Irvine is competent with more than one firearm

e; Irvine's breakdown is dumb, but it's dumb because you probably want to send a hardened, experienced veteran to assassinate the most powerful and dangerous person in the world, not a kid. But this is a world where mercenary outfits take the place of conventional K-12 education.

e2; A properly used whip would be a really dangerous weapon, they're just really hard to use properly. If you're using some space alien magic FF bulltrout like Quistis then it makes sense it'd be fairly powerful. This holds true for every weapon except Zell's fists, but Zell is second only to Sabin for sheer goddamn badassery so what the smurf do he care?