Can you use TAG and Arrow IV homing rounds under Standard rules?
Target: Artillery, when used in direct-fire mode, can target either a unit or a Point of Impact (POI). This POI is selected on the map, and an area of effect template is placed at the final POI to determine which units the artillery damages. If the to-hit roll succeeds, the POI selected is the final POI. If the to-hit roll fails (the attack misses), the POI will scatter (see below).
Artillery fired indirectly can only target a POI.
It might be arguable that Arrow IVs have an inherent "switch" capability to be fired as either regular explosive rounds or homing rounds without resorting to optional munitions, but that language resides in the Advanced rules section for Artillery which I believe might be rendered moot when Standard rules are in play. Even if Arrow IVs can freely switch between explosive and homing missiles turn by turn without having to make use of optional munitions, the bolded section of text in the quote seems to preclude the option anyway.*
*EDIT: Barring the obvious possibility: Using TAG to guide in rounds fired directly rather than indirectly. Although that seems soundly legal, it seems wonky and shouldn't be correct when IF TAG guidance is prohibited. Both or neither is how it probably should be.
