Admittedly, CDR from blue helps anybody. But yeah, I did that once by accident, early on. It was just "Oh look a friend is fighting a big rock guy. I WILL HELP U FRIEND! HEY WHAT ARE THESE FLOATY BLUE TINGS ROUND ME?" >_<
Why is it lately that any game where we have a Kennen, he turns out to be a total douchebag? Laned top with one as Taric, intent on playing pure support. Stuns + heals all day long. Dude starts raging when Ahri shows up to gank and gets the kill. Then starts raging at me when I wade in to help out with my big blinghammer and happen to get the last hit. And when I tossed a stun at a fleeing Ryze and happened to stun him just a wee bit too hard and killed him. And when I had done 60% of the damage to someone already, he tosses a lightning at someone, and then I hit and kill them and he just about lost it. Finally (after fair warning that I would do this the next time he bitched), I just stood there and let a near-dead Sona flutter right by me as he desperately tried to chase them down and got waxed by the tower, just to prove my point.
Don't piss off the support, they're ON YOUR SIDE. I love playing support in most games, but I can understand why people get sick of it in LoL. In most games, your teammates are thrilled when you heal them, debuff the bad guys, buff the good guys and can toss your own meager firepower into the mix. But not here.