This is a
phrase that was found useful during the days of the
BBS and the
1200 baud modem when certain BBS software would censor potentially
offensive messages based on
language.
If the filter option was turned on, it would often disallow words such as cock, pussy, suck and related.
So, even though you wanted to talk about the Year of the Cock, you'd have to rename it the Year of the Rooster. And if you were referring to your sweet little pussy cat, you'd need to use the word kitty instead. Finally, if things just downright sucked, you couldn't say so. Heck, you couldn't even say a vacuum cleaner sucked.
Thus was born the phrase "inhales violently." This would be modified depending on just how much suckage was going on, with particularly bad suckage changed to the much more inoccuous "inhales most violently." While not all BBSes had their filters set, many users belonged to many different boards and rather than try to remember which was which, they would use the phrase universally, thus spreading it like a verbal virus accross the networks.