same here, been doing a lot of EBG on horde and didn’t met any premade yet, when we constantly met ally premade aka pandora and larkus during s3 and s4.
A lot have been said on the forum already, you can go check this thread for example: Another "premade post"... :/ - #152 by Pandòra-draenor
You will find almost all premade leader saying that blizzard “have made an official statement, that sync queueing is not against their rules or code of conduct”
So good luck with this fight I hope Blizz will finaly do something one day