So...for those that don't know...Grenadier Alchemists with the Explosive Missile discovery can spend a move (later reduced to swift, later further reduced to free) action to attach an alchemical item to an arrow (or other ammunition) and spend a standard action to attach an alchemist bomb to the same arrow, and fire it at a target.
Under RAW, you can't add Vital Strike to that due to competing standard actions, I get that. The house rule in effect is that you can add Vital Strike any time you are limited to one attack for any reason (generally meant to allow Vital Strike on charges, but I'd also allow it to apply to Spring Attack or other similar situations).
So...with a bomb, a flask of acid, and a bow, what's the general opinion on the effect of Vital Strike in this self-inflicted situation? I'm the GM, and I'm leaning towards only allowing it to be applied to the bow damage, but I'm curious if others have a reasonable argument otherwise.