Some people seem to be having trouble understanding the Alliance system and the splitting of points so I will try to lay it out here.
Scenario 1: two smaller guilds team up.
Guild A has 5 EU timer players.
Guild B has 5 EU players.
Guild C has 10 EU players.
A fort is worth 200 points, divided between 10 players is 20 points.
All 3 guilds go after the same fortress.
Guild C wins as guilds A and B are split. Guild C gets all 200 points.
Guilds A and B ally creating the organization AB.
All 3 guilds go after another fortress but now that A and B are allies they match and beat guild C and take the fort together. The system recognizes that the organization AB has taken the fort and members of the organization can both access the fort. (use the doors, loot the chest, etc...)
Organization AB gets 200 points for taking the fort. there were 10 players involved, since each A and B contributed 5 players Guild A and Guild B both earned 100 points and now those two pots of 100 points gets put into the alliance equation: 1/2A + 1/4A+1/4B = Guild A's share (1/2 of 100) + (1/4 of 100) + (1/4 of 100) = 50+25+25=100.
So by allying guilds A and B get 100 points where otherwise they would get 0 as individually they could not compete with Guild C.
So: If both guilds work equally hard they can get a slice of a pie they otherwise would get none of and share that slice equally.
Note how a guild that is all EU players and another that is all NA players could also benefit from an alliance as together they can hit all the forts and get a piece of each while holding them from other guilds and being able to support each other in defense should schedules align ( like on weekends or holidays)
This is the ideal but not likely to be the case in game.
Scenario 2: Un-even contributing alliance
A has 7 players. B has 3 players. C has 10 players. Fort worth 200 pts.
Alliance AB wins fort. A contributes 140 pts, B contributes 60 pts.
A's Share = 140/2 + 140/4 + 60/4 = 70+35+15=120
B's share = 60/2 + 140/4 +60/4 = 30+35 +15 = 80
In effect A pays 20 points for the alliance which allows it to get 120 points and the fort where otherwise it would get 0 and Guild C would get 200.
As the season plays out A will pull ahead of B if things continue but instead of the end rankings being 1st C, 2nd A, 3rd B the alliance allows A to get 1st place, B 2nd, and shuts out C who gets 3rd.
TLDR: Alliances allow smaller groups, or groups in different time zones, to compete with larger groups.