The longest stun is worthless, if it never hits. A 5 sec aoe stun sounds impressive, but most of the time you're hard pressed stunning a single enemy in pvp, let alone two. If it's numbers you want, look through all MoP arena videos you can find involving shaman and compare how much CPT actually hits in higher ranked matches vs. Deep Freeze, Cheap Shot and co. We both no you wont bother going to such lenghts just to prove yourself wrong anyway. We both know CPT is hard to make work and close to worthless in high ranked pvp. The higher the demands on an ability, the more worthless it becomes if it is heavily limited in usage.
I dont really need a factual argument to prove that CPT is at the bottom of the stun-barrel, but if you insist:A look at the tool-tip, the fact
that unlike other stuns, CPT has the option of two glyphes and one talent to enhance it (if it were as powerful as you make it out to be, it wouldn't require those to exist, right?) and last but not least, common sense. With common sense, you will notice that CPT requires a baby-sitter. Unlike a Warlock's cataclysm though, it is our only stun.
Are there glyphs shortening cataclysm's charge up time? No, because it is useless anyways and nobody would bother glyphing it, since warlocks got a shitload of CCs and stuns even without cataclysm.