I think the matches were actually quite close, but SSW's play style masked it. The high aggression pick and skirmish comps they use fall off really hard late and are terrible at 20+ mins without a huge lead. They had to win as fast as they did, or else they would have just fallen apart. SHRC took advantage of this game 3, and could have won 4 were it not for the terrible gank bot and the dragon fight where InSec started his ult right next to Janna.
I think that the main problem for SHRC is that they rely on InSec's ability to get picks in order to stall out the game, as their solos are terrible at pick-focused champs. Since InSec was forced onto KhaZix for two games (who has no hard cc and has horibble burst compared to Rengar or Lee Sin), he could not perform that job. They should have put InSec on Eammus or Panth earlier, instead of waiting until game point.
Still, it was great to watch SSW push their strategy to the edge. If there isn't a SSW Rengar skin soon, I am going to be very surprised.