I'm a Soraka main, and I've noticed an interesting _interaction_ when I play against Braum in the bot lane. Mind you, this happened in 3 different games, 4 times in total, with every new time it happened making me more certain. Let me explain.
You know when Braum starts walking towards you, you see his smug face, you know he is going to ult. So *pop* goes the Silence, right at his feet. But he ults anyway. I say, I must have had high ping.
Second time, he starts approaching, I know he wants to do it, I silence him again, but he pulls it off again. Maybe this is a bug, I wonder?
Third time, he "hops" with that spell of his, **right** into a silence zone, and ulties from there! Now I'm starting to get a little salty. "Why are you unfair to me Riot" and all that.
Forth time, he stands in the silence for what _feels_ like eternity. He ulties. He finishes ulti. And he actually gets rooted in place. So, he stayed in the zone for the full 1.5 seconds (because that's when the root happens) and he pulled off his ultimate as well.
So here I am, bug reporting and all, hoping that this is some sort of oversight between those two champs, although, Soraka's silence in general is _spotty_ at best. Most of the time, it takes so long to **actually** activate, that Kata ult has killed 2 allies already, before she _finally_ stops spinning! :P