It's not the spectators that seem to cause the problem xen and i are experiencing.
The real problem imo are too many players on 1 crowded map this problem also starts it's other flaws of the game/server (too many nades,heavy weapons, atillery, airstrikes and teamdamage.)
Xen solution might actually solve the problem but it's probably something legacy or the server isn't capable of doing?
And ofcourse there is also the question do u really want to change stuff to the server because the server does get alot of players, but with this problem i do notice people leave the server because of it.
If there would be like games like 10vs10 it would be managable for all players everybody got his liking imo. But when there are too many players it kinda ruins the game for everybody.
But i must say it really pleases me to see the server still gets this much attention.