Sorry if this has been answered before. Can a trooper fire an impact template weapon at a valid target if the template also catches the firing trooper (but no other allied or neutral troopers) under it? Does it count itself as an 'allied trooper' and get the template cancelled?
Allied trooper is a specific terminology. The trooper belong to the same army as the trooper itself; yes the trooper is allied to itself. I know that in previous edition it was argued that you could pick a time of attack when the allied troopers were not in the attack area to avoid clipping them with template - provided they moved outside the template during the order - but I don't know if this still holds water as they seem to have removed the example with the Fiday in this edition (or at least it's not linked to Template Weapons)
Is that just referring to the 'direct' template though? because that one HAS to be touching the firing trooper.