Many of the problems the Wehrmacht had were due to Hitler's interferance, especially on numerous occasions in the Eastern Front.
As far as artillery being their own divisions, whoever stated that artillery only operate in assistance of other divisions hit the head right on the nail. You're not just going to have a bunch of artillery sitting out somewhere alone with no supporting forces pounding away to cause some effect... the artillery is either softening up the advancing enemy, or weakening their lines for an assault of their own. Artillery rely upon the usage of other arms to be effective.
To say that corps/armies/army groups aren't a part of HOI is just a matter of opinion. Some may say that the HOI battle system is way too abstract to actually be representing that sort of thing, but I think it is. Sure all you can do is group divisions into a larger more easily managed group, but then you can manage the stack of those corps/armies which may form abstract army/army group type units. That's how I view the situation... when I'm about to invade Russia with 100 divisions, I don't see a big lump of 100 divisions scattered out, I see armies which are independent and capable of working on their own for objectives. I take the time to name each accordingly as well... "1st Panzer Army, 5th Shock Army" (two of my favorites and most effective that I used while combating the USSR and Netherlands... yes, the Netherlands, don't ask
).
It all depends on how you look at it.
As far as artillery being their own divisions, whoever stated that artillery only operate in assistance of other divisions hit the head right on the nail. You're not just going to have a bunch of artillery sitting out somewhere alone with no supporting forces pounding away to cause some effect... the artillery is either softening up the advancing enemy, or weakening their lines for an assault of their own. Artillery rely upon the usage of other arms to be effective.
To say that corps/armies/army groups aren't a part of HOI is just a matter of opinion. Some may say that the HOI battle system is way too abstract to actually be representing that sort of thing, but I think it is. Sure all you can do is group divisions into a larger more easily managed group, but then you can manage the stack of those corps/armies which may form abstract army/army group type units. That's how I view the situation... when I'm about to invade Russia with 100 divisions, I don't see a big lump of 100 divisions scattered out, I see armies which are independent and capable of working on their own for objectives. I take the time to name each accordingly as well... "1st Panzer Army, 5th Shock Army" (two of my favorites and most effective that I used while combating the USSR and Netherlands... yes, the Netherlands, don't ask
).It all depends on how you look at it.