I'm just curious, was there a stated reason anywhere as to why they changed from centralized to dispersed strats? People don't usually make changes arbitrarily, so there's seemingly some behavior/gameplay they'd like to not be emphasized, or the centralized strats weren't promoting the sort of gameplay they envisioned when choosing to centralize them.
My .02 on this, although HiTech would be the best source for actual explanation.
1) Let the red guys take your zone base and your strats are hidden far to the rear.
2) Do not attempt to re-capture said field as it would move your strats back towards the front.
3) Don't take the enemy zone bases as it will move their strats to the rear.
4) The enemy will not attempt to defend or re-capture said field as it would move their strats towards the front.
Putting it simply it creates a situation where avoiding combat is the most rewarding choice for the country you are flying with.