I only want to say that rain in CAP metagame is really really broken, because it aids three of the mos prominent pokemon in CAP: Tomohawk, Cyclohm and Necturna.
EVs: 252 SpAtk/4 SpDef/252 Spe
Rain boosts Hurricane's accuracy so you can abuse it with no regrets, not only that, but the Fire type move's reduction in power allows Tomohawk to wall Infernape, Heatran, some dragons (If you sub on Draco Meteor as they wont be able to attack you with Fire Blast for example, and Tomohawk resists Focus Blast and stuff), and many others it didn't wall before, with maximun invest into special attack it turns not only into a defensive pivot, but into an offensive threat.
Cyclohm @Life Orb
Trait: Shield Dust
-Draco Meteor/Dragon Pulse
Big threat, big big big threat to today's metagame, there is very little that wants to take 100% accuracy Thunder or Rain boosted Hydro Pump to the face, and some of those who would like it are decimated by Draco Meteor/Dragon Pulse, Shield Dust makes it a perfect switch in to bulky waters and Specially Defensive Jirachi, and its bulk allows it to take water and electric type moves and just Slack them Off, really powerfull indeed and you can even run Fire Blast to 2HKO Ferrothorn in rain.
-Any set you want!
Add to the fact that Necturna is already very unpredictable and hard to take down due to her bulk the Rain to weaken fire type assaults, according to sets it could even beat Heatran one on one! It's like taking a weakness from her.
As you can see rain is really overpowered with CAP as it is now, I used a Rain team with bulky spinning Necturna, Tomohawk and Cyclohm and it got me really high in the ladder, so try rain in CAP it really works!