I can agree with you that spalling was and is a major factor in tank crew survivability. I am not, nor do I even pretend to be a computer programer. However, I would assume that it would be difficult to model spalling in tanks without a major amount of work. Do you want a set number of spalling fragements to be modeled given a certain penetartion table, or do you want a variable number of projectiles determined by a host of factors? Let's assume that you want a set number of fragments created by spalling to be modeled (call it 5). Now that you have that down, how do you want to model the way the spalling interacts with the inside of the tank? Are you going to model a set way they fly out from the impact point, or are you going to make that a variable? Are you going to model a set patern of richochettes, or are you going to make that a variable model too? Are you going to model every crewmember and their exact position in order to determine if they get hit, or only a couple of "critical" ones? And if you are only going to model a couple of them, how do you determine who is "critical" and who is not?
Look, I agree that the damage model isn't perfect, but I would think that modeling spalling would be a huge undertaking that would detract from the amount of time HTC would have to model new planes, not to mention AH2. I would also like to see ammo storage areas capable of brewing up and engine fires that could damage or even destroy a tank. While I would like to see these implimented, I can also see how doing so would probably take a lot of time and effort, and that the game engine would probably have to support that as well, not to mention the system requrements needed to compute all of that in real time. Instead, we seem to have a damage model that is location specific: if you get a penetration in a certain location, you kill the tank/engine/main gun/track, ect. While I have read that some people can't kill tanks when hitting them in the locations I aim for, I CAN say that I do not seem to have their problem. I have not observed any of the strange occurences that others have mentioned. Maybe I'm just lucky.
While I agree with you there is room for improving the ground vehicle damage model, I can also understand why it is the way it is.
As for information in regards to crew/tank survivability when penetrated by an enemy shell in excess of 14.5mm, I'll have to check. I do recall reading a book (don't remember if it was from "Death Traps" or "Marine Tank Battles in Korea", or another book entirely) where an enemy shell was found lodged under the driver's position after the tank had been engaged in combat with some enemy tanks. IIRC none of the crew were hurt, and the tank was fine.