Okay,
The 2 targets to attack and 2 targets to defend problem:
In theory, the CM wants the CiC to defend both and attack both. If the CiC wants to get 100% of possible points. He has to do that. With 30 people on one side (sum of 60 people), the CiC has to split his forces into 4 groups (7-8 each). Now he has his first problem. He has small (4-6) and big squads (7-10). Secondly, it's a directive to concentrate forces. If he concentrates his forces, he can't defend both with same strenght. The attacker on the other side, doesn't want to send his troops to a target and being outnumbered by defending forces. He concentrates his attacking forces therefor. If you split your forces for attacking/defending 50:50), that means ~15 people. If you have bombers, you need to have at least 4 of them (order by CM) and put the rest into fighters. If the CiC wants to attack both targets at the same time with 2 different forces, it means 4 bomber/jabos and 4 cover each.
Those 8 attackers will met now the defending forces. In theory it would be same strenght, but the cover would be outnumbered already 2:1. If the attackers are lucky, the defending forces have been concentrated and therefor they will meet small or even no defending forces. If it runs bad, the defenders have been concentrated right at the attacked field.
Now, if the defenders don't stay over the field waiting, but CAP the front area to intercept attacks before the field and the attackers use front sweep, they both have to concentrate their forces even more, which brings us to the next problem. If you concentrate again, you end up with 1 attack group and 1 defending group. But if both do that, the defenders again outnumber the attackers, which brings us to the next step of concentrating, the CiC decides to be "aggressive" and puts all of his people into one big attack group, hoping that he will be better in attacking and that field acks might do the defending.
And there comes the other problem. What if both, put their troops into attack? 2 possible ways can happen then. They meet half way in a big furball or they miss each other and probably meet on their way back or never meet. That would mean, that the one who killed more and lost less to field acks wins.
I saw all of the above described happen in sunday SO and I don't liked it.
That's one reason why IMO "Channel Wars" was better for small forces, because only one had to attack and one had to defend. It works great for smaller numbers. For big numbers 200+, you risk the big kludge effect (concentrating forces into one big furball) by CiCs concentrating their forces. So, you divide up forces by assigning targets to attack and defend. And there it works.
And that's the reason why Friday and Sunday are different. They need different designs as long as the numbers very low on one hand and big on the other.
This is my personal analysis of the situation. Not everybody will agree and I don't say I'm the one who is right, but I saw all the stuff I described above happen and I think it was for the reasons I wrote.
I hope I didn't step on anybodies feet. It was not my intention and I hope nobody takes anything written above personally. Remember I'm not native englsih speaker, therefor might things sounds different than I mean them.