Yeah and that lets it counter bulky waters unlike the listed pokemon. Nasty plot wouldn't do that so well because it would hit there strong Special defense. Your not even trying to take adavantage of moves that toxicroak has and infernape lacks ; your using cross chop, hp fire and sludge bomb which is a rather poor offensive type for ou with all the steels running around and cross chop and Hp fire are completely inferior to flamethrower and close combat. Also infernape has a immunity to will o wisp which means it will never have problems getting through blissey. The reason Toxicroak is viable in ou is because of it's water killing niche without slowing offensive teams down and even outside of that is handy for stuff like choice scarf users weak to sucker punch such as gengar.
Okay, I have a serious problem with just ignoring shit because it doesn't look as good on paper.
For starters, this poison sucks never use it bullshit needs to stop. Poison / Fighting STAB is actually very good, only resisted by Tentacruel and Gengar in OU (oh well you look at that Tentacruel can't fucking touch you)
Secondly, Nasty Plot hits harder than Swords Dance to begin with because of the physically based Metagame. The things about Infernape are irrelevant since Swords Dance / Cross Chop / Sucker Punch / Stone Edge is still inferior to Swords Dance / Close Combat / Stone Edge / Fire Punch, Flare Blitz, Mach Punch. Since I have no idea what I'm talking about, considering I've used both SD and NP Toxicroak and found Nasty Plot to be WAY more efficient, peep these (I even bolded the OHKOs with SR just to highlight shit):
Toxicroak (M) @ Life Orb
Ability: Dry Skin
EVs: 252 Spd/252 SAtk/4 SDef
Timid nature (+Spd, -Atk)
- Nasty Plot
- Sludge Bomb
- Focus Blast / Hidden Power Fighting
- Vacuum Wave / Dark Pulse
---
+2 LO Sludge Bomb vs.:
Min / Min Gyarados: 87-100%
156 HP / Min Gyarados: 78-92%
Max / Min Gyarados: 73-87%
Max / Min Vaporeon: 67-79%
Max / Min Suicune: 63-74%
Min / Min Suicune: 75-89%
Max / Min Zapdos: 82-97%
Specially Def Zapdos: 60-70%
Max / Min Rotom: 44-53% (2HKO w/ SR)
+2 LO Focus Blast vs.:
Max / Min Vaporeon: 89-100%
Max / Min Suicune: 84-98%
Max / Max Skarm: 100% (114% minimum)
Max / Min Blissey: 83-98%
240 HP / 52 SpD Swampert: 99-100%
Max / 88 SpD Hippowdon: 100% (113% minimum)
+2 LO Vacuum Wave vs.:
Min / Min Lucario: 100% (121% minimum)
Min / Min Infernape: 65-76%
Max / Min Scizor: 45-53%
Min / Min Naive Scarftran: 84-99%
Min / Min ScarfTar: 100% (150% minimum)
+2 LO Dark Pulse vs.:
Max / 136 SpD Rotom: 94-100%
Yeah, I'll let the numbers speak for themselves. If Swords Dance can post the same efficiency, then ignore this set, but since it can't, Nasty Plot should obviously be given an OU set.