I don't think that a new patch is going to help the premade situation. From what I can see, it is the players themselves who are hindering premades. There seem to be 2 groups of people who premade in this bracket:
Group A: Wants to premade for fun and activity.
Group B: Wants to premade to be #1 guild.
Guilds in Group A quietly enjoy their premades and don't make a big fuss about them on TI because they are for fun.
Guilds in Group B don't want to premade because they worry about losing. If they do premade and lose, they bicker to no end about excuses for losing. Guilds in Group B start calling guilds in Group A bad.
If a guild in Group A loses a premade, guilds in Group B call them "bad".
If a guild in Group A wins a premade, guilds in Group B still call them "bad" because they call the other team "bad" as well.
Over time, Group A gets tired of Group B calling them bad and loses interest in premading. End result: no one premades.