False you say False! What is false and how do you know its false please enlighten me but let me
enlighten you first.
This ought to be good!

J/K
The whole point of getting the Planning bonus is because you have trained and prepared to achieve a series of objectives (Offensive Front-Line)
It does not have to be a "series of objectives" it can be a single objective. A single provence a single state a single objective. So when I say FALSE sometimes it means that your terminology is not correct. I can't agree or not disagree when a statement like "a series of objectives" is stated. It gives the wrong information.
so its more then stupid to allow that bonus to simply recover whenever you halt a Division as it would defeat the reason for having the bonus and would mean the actual Offensive Front-Line itself would lose its relevance and importance.
If you "halted" a division that would mean that the division actually ....... moved. You can't halt something that has not been in motion. So when you put that into gameplay action..... it would mean that the actual Offensive Front-Line actually moved and was not stagnant.
If indeed you could halt a Division any time you wanted and regain the bonus then it would require manual intervention by the player because unlike some people I do not believe anyone in their right mind would attempt to program an AI that can ignore the Players instructions.
Correct. The human will always over-rule the AI.
The only logical conclusion is that once you initiate a Plan the bonus will tick down and it will not tick back up again until you reach the Offensive Front-Line
As stated in the above paragraph you the human can stop a division or divisions (or anything you like) to have them begin to regain their planning bonus. The bonus will begin to increase when the troops/tanks etc. have stopped. They have to be motionless to increase the bonus.
The AI will always follow the Players instructions to reach the Offensive Front-Line and if the player does intervene and halt a Division the bonus will not tick back up or at least it should not tick back up but you never know the daft things that people end up doing.
I don't know what daft things you are talking about however you are correct that the planning bonus will not increase until the units are halted. Either by the human stopping them or they reach their assigned goals within the planning bonus that you the human designed. When units are stopped their bonus will being to tick up again. They can reach the battle plan objective and have it begin to tick up or you can stop them before they reach their objective and have the battle plan tick up. You are in complete control. 100% control.
Perhaps your right and no one needs to give a monkeys fart about the location of their Offensive Front-lines but that would be extremely disappointing so once again I will ask Paradox for clarification about the Planning bonus........
Yes and no. You as a brilliant Field Marshall will be looking at your troops and individual battles along with master plan itself. If you see some of your divisions being beaten or not moving as fast as you wanted or having a difficult time moving through difficult terrain just like in HOI3 you as a brilliant General will do what it takes to achieve your goals. Whether it be, sending more troops, more planes, redirecting troops from another part of your offensive front, calling up reserves etc.
Once you launch an Offensive your Planning bonus starts to tick down when does it tick back up again?
When they stop. Just think of real life in the field. Your troops move 3 provinces. They fired 12,000 rounds, 14,000 shells, suffered 100 dead & 1500 injured. They 'may' have to stop to wait for reinforcements, ammo, water etc. Just like real life. Eventually an army will run out of things as they move faster and are further into enemy territory than their supply lines. Makes sense no?
1\ When you reach the Offensive Front-line?
When and where ever they stop moving.
2\ When you reach the Offensive Front-line and you have a second phase to your Plan?
It is just the act of stopping to re-arm, re-fuel, re-up manpower, etc. You don't have to have a second phase (which is why I said FALSE to your previous post). You may just want to stop right where you are.
3\ Any time you want just manually halt your Divisions? I assume on a scale of 1-10, 10 being the most stupid this is a 10.
Like I stated. Picture your forces in the field. In actual battle. They don't have energy weapons that never run out of ammo. Your soldiers are not machines they do require supplies to keep fighting.... food, water, bullets, shells, replacements, guns etc. etc. etc. Therefore in some battles against a really difficult opponent they may have to stop more than once to get supplies. Then again a country like Germany attacking a country like Albania well do you really need a battle plan for that?
The battle plan is totally optional. You don't ever have to use one and still conquer the world! Or you can make a battle plan that advances just one province at a time. Then stop, regain their bonus and then march onto the next province and stop again regain their battle bonus etc. etc. etc.
A battle plan can be as large as Russia or as small as Wake Island or anything in between. It is 100% flexible in that the human, you, are in charge of every single aspect of its implementation, it's changes it's intelligence gathering. The AI works for you.
Cheers