Tribalism also tends to centralize anyway, just as it did to give us the two major parties we have now.
The incentive will always be for the smaller gangs to consolidate to gain more power. Four will just become two again once people realize that winning on the big issues is more important than losing for the minor differences between a given set of smaller gangs. Purity tests return, as they always do with tribalists, and we are right back to trying to have more gangs to fix the problem.
Parties and collectivism are the actual problems in my opinion.