I've seen and heard lots of discussion about those terms over the years. Here's my two bits worth: From my dad and my uncles who were pretty good cowboys, they implied that the holihan was a type of loop, and deft throw, that was used when roping horses. When you've got a corral full of circling horses just wrangled (gathered) early in the morning, they're pretty skittish -- especially if you're working in a temporary round-up corral that is just one waist-high rope stretched though iron stakes. Consequently, rather than making a big loop and using a flailing, swishing sounding swing, which would excite the horses even more, the cowboys developed a "horse loop" that is a short, smooth, overhand toss with a hole in the rope just big enough for a horse's head. I believe this is the "holihan". As for firey and snuffy, I always assumed those were the typical western jargon for the emotional state of the horses and/or the cattle. Horses and cows regularly "snort" loudly (and fart, too) when excited or disturbed. If you've ever had a mad cow blow snot in your face, the term "snuffy" fits ! Firey means high-strung, or nervous, which fits the line "The firey & snuffy were rarin' to go".