Please do not misunderstand me. My purpose is not to say that this game sucks or that people who give effort for this are doing poor job.
This timing issue was not (is not? Will not be?) perfectly clear to me and the provided answers did not satisfy me. I decided to give my point of view and wait for clarifying replies, which I have got.

I personally believe that objective and critical discussion is the best way to stay in the right path. If you find yourself in a situation where the only argument left is “That’s just the way it is”, you know that you are in wrong direction with big probability. I hope my favourite game can find a right path whatever it will be.
I still have few questions
Special Opfire is used to compensate the lack of AI intelligence and especially to simulate asynchronous battle conditions, right?
Asynchronous battle conditions
When Special Opfire is used to simulate asynchronous battle conditions it means that time in combat situation is measured by the amount of units that can trigger Special Opfire?
-More attacking units = more time to spend (return fire).
-Time is a function of triggering units.
The problem(?)
Time is not a decreasing function of units triggering Special Opfire?
If not:
-A unit can have an infinite amount of special Opfires? E.g. take a Flammpanzer III and put it next to ammo dump…it can fire over 30 times

…only limiting factor seems to be the available ammo.
-If firepower differential between two units is big enough and bigger firepower is elite unit already with considerable rate of fire (Flammpanzer III vs. infantry), one cannot increase the probability of an successful attack by increasing the number of attacking units

-There is ot difference in achieving synchronization whether you use elite forces or not.
-Events (fights) are independent from each other in time, so the battlefield is absolutely asynchronous and you cannot synchronize your forces at all.

-A forest consists of large number of individual trees that must have some binding constraint between them (time & space)? If trees are represented individually in time or in space they cannot form a forest?
I understand (hopefully) for what the Special Opfire is used and I welcome it. But the extend in which it is used is in my opinion way too much. At least the time should be a decreasing function of triggering units (if it is not). The slope of the function is a subjective issue, I would prefer steep slope and try to find other means to create asynchronies.
Disclaimer: following text is just thoughts and may not have any sense at all
In order to model better the difficulties of synchronization one should keep the time constant and have random variation in unit performance rather than keep the unit performance constant and have variance in time?
Why not use something like the combat friction when determining the movement?
Units could have probability distribution that gives random values for the movement?
That distribution would be affected by different variables like unit characteristics, weather, suppression, command, terrain, etc?
This way one would get variation in movement which would be more much realistic way to raise the difficulties of synchronization?
One would need to measure movement more accurately to make it work? If infantry moves four hexes the minimum change in movement is 25%.
-Change the scale. E.g. double the movement points and make bigger maps accordingly
-One would get min. change 12.5%
//We all know how crucial the timing is in a battle.