This is not true, arty can still be taken out by directly targeting the gun. The grace provided to weapon teams does not apply to arty. When you see arty target the gun.
On a side note the IL-2 bombing run often decrews the gun and then another bomb hits destroying the low health gun. This may need to be looked at. On the other hand IL-2 is vulnerable to AA, warns the targeted player, and is slow to arrive.
How do you target the gun with a Stuka Zu Fuss barrage because I need to know, thanks in advance.
EDIT: And you can reduce the howitzer to 0 health but if the crew is alive it won't die; Iv had LeFH's with 0 gun health before but because I had a command tank and a bunch of reinforcement and healing bunkers they couldn't kill a single one.
Targeting the gun does nothing unless the crew dies. Sure you might damage the artillery piece but if you can't kill the crew...