User blog comment:Xyclone010/What's the matter with CC?/@comment-1600221-20140927075405/@comment-25055281-20140927123721

This and more

In the cases of Kassadin and LeBlanc it was not just uncontestable burst, but also free harash (targeted silence and a shield, targeted silence on a ranged champion)...get your opponent low before 6, and then easily kill him with your ult.

Talon is AD, so harash wasn't free, but he could trade hard with the silence and then lifesteal his health back...again, easy kill at 6 (or at least lane dominance)

And the key point there in my oppinion was that those were targeted, non ultimate and instant or almost instant abilities (LeBlanc having to click twice on you). Fizz's Chum the Waters is a skillshot ultimate with a delay on the damage, Zed's Deathmark is a delayed damage ult and Ahri's Charm is a linear colision skillshot (minions op) to name a few examples. Those can be countered, either by dodging (this is for Charm), burning scapes to get away from some damage or with a well timed Zonia

tl;dr targeted silence + movility + burst = bad (or too good, depends)