Question: Use of Assault Artillery (or Tank Guns in general) against Infantry

[jp10]

I think the game simulates well that plunging HE fire (Arty) is more effective against Infantry than open sight direct fire. Assault Guns were ideally for attacking bunkers, MG nest and (in some armies) laying smoke. Against light defenses, they could be used as moving shields for Infantry to advance behind.
Use them as moving MG bunkers to lay a base of fire and save the HE for fortifications, improved positions and crew served weapons emplacements.