People who say 'CC > everything else' are like young boys who discover masturbation and decide it's the best thing ever and that they gonna dedicate the rest of their lives to furiously jerking off.
Sure, it has quite good pleasure to effort ratio, but there's more in life than that.
@Jim-Cojones
I'm definitely not arguing that sona is bad support. But Nidalee has utilities that Sona lacks - long range poke/bush checker with spear, trap that lowers resistances and which can serve as miniward for small bushes, little heal with huge AS steroid, godly juking ability and decent burst in cougar.
And best part of Nidalee's heal is not the heal itself - it's the AS buff that gives huge damage increase for your ADC.
CC is one of the most important, if not the most important, aspect of supports kit.
1. In laning phase, the job of support is to protect the carry from aggressive plays, harrass, sustain and make kill-winning plays. Having CC is crucial for both saving carry's ass and securing kills.
2. Post laning phase, depending on your role in team, you'll either initiate or stay with carry and peel for him. You can't initiate without CC and peeling is very hard, in case of Nidalee it's limited to healing for pitiful 200hp.
3. Supports need to scale without having many items and having some sort of CC is one of the best ways to achieve that.
I definitely disagree with a statement that CC the most important aspect of support kit. It's strong aspect that's is always useful - but if other members of your team have plenty of stuns themselves then you'd better off with things that would nicely cover the weaknesses of your team's composition - be it sustain, long range poke, map awareness - rather than stacking CC.
Ad 1. The job of the support is to support. Having CC is one way to do it, keeping him topped and buffing his damage (via AS) is another. As of securing kills, well... in laning, more often than not, Nidalee is gonna grab a kill herself instead of donating it to her ADC, but I'd say it's pretty hard to escape the pouncing cat, so kill is quite secure in her paws. On the other hand, Nid can make better use of the items than most of the supports, so it's not that big of a deal.
Ad 2. Or you can do other useful things like: poking, buffing your ADC, keeping enemies scouted, reducing resistances of enemy bruisiers, baiting like a boss, helping bursting down enemy's carries. If you're good you can even do most of those things at the same time.
Ad 3. Sure, CC is a good way to do that, but Nida has no problems with scaling herself - her Q has bonus scaling with range/missing health, trap reduces resistances by % of total, AS buffs scales with your carry AD.
