You cant call it "hacking" when you dont know how its done.Not supported doesnt mean they have to do some workarounds.We dont know.
As for the Sb850 requirement,its a MAYBE.Asus will introduce mainboards even with a 760G northbridge,but we dont know yet with what southbridge theyre gonna be paired up.
And even if.Thats not a bad thing if all Sb850 mainboards were compatible with AM3+ cpus, now would it ?
As to why only asus ones were built properly, i dont know either.Maybe some others are too.Or maybe AMD wasnt interested in getting backwards compatibility so it wasnt part of the standard.Or maybe mainboards manufacturers did it on purpose to sell more units.Or maybe thats all true.
One thing is for sure, if AMD would sent new AM3 specs to mb manufacturers and enforced them through some press release.All MB makers would have to comply or be hit with lower sales due to less features.