Weapons (bombs) are subject to delivery and ballistic error. These error's are/can be both internal and external (pilot error, a bent fin, weather etc).
There is a tremendous amount of time and effort on the part of mathmaticians, ballisticians, and statisticians that goes into figureing the dispersion (or error) of bombs...even with our modern day PGMs (GBU, LGB, etc etc).
All bomb/target combinations (today) whether it be single or multiple weapons, guided or unguided against point, unitary and or linear targets, end up with a "Probability of Damage" that incorporates weapons effectivness and target "hardness" (and target location with todays PGMs) that is not always as entirley precise as some folks would think.
Simply put, there are many approaches HTC could take to figureing "bomb dispersion". I would guess there will be some kind of general pattern in which bombs (multiples or "sticks") will fall while single bombs will have some randomness (for lack of better word) added for the sake of realism.
Someone said earlier in this thread that even in World War II we had a relatively high capability for "precise" weapons delivery. I have to disagree. Even today's so called "Precise Guided Munitions" or PGMs don't always get where they are supposed to...this is error in a more technical sense but error (or dispersion) either way you look at it. With dumb bombs...and I've seen this, all the science and technical details really help the situation, but as often as not, good ole' Kentucky Windage render's the same results

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