> All bees travel the colony pretty much all the time.  
> This gives them a decent assessment of its size, 
> state, resources, and season-adjusted needs.  
> Then, they respond to the needs.

Studies were done (as described by Gould and Gould
in their book) where the bees had no ability to get
to, walk on, or inspect empty drawn comb, yet the 
presence of the empty comb still had the effect of 
prompting more foraging sorties than control colonies
with far less empty comb.

So, it is comb pheromone that "informs" the bees as
to the state of their larder, rather than individual 
inspections by each bee.  Ditto for brood pheromone.
The new "Bee Boost" product claims to enhance pollen
foraging with the chemical alone, something that would
have no effect if bees were wandering around counting
open brood cells or estimating brood area themselves.

Also, if you mark bees when they emerge in an observation
hive, you will find that younger bees do not enjoy
the run of the entire hive, but tend to stay in their 
age-appropriate "work areas".

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