>>Why would adding combs lead to a faster buildup? 
would "checkerboarding" cause the queen to lay more eggs?

Yes.  Checkerboarding the broodnest - 1 empty comb at a time every few days! - artificially enlarges the broodnest.  To be safe temperature-wise, I only leave sealed brood on the outskirts of the broodnest when I want to have colonies catch up.

If broodnest checkerboarding is not done, the queen will go ahead and lay around the outskirts of the broodnest but, if the bees feel that's too many eggs to handle, they will eat them out.  Checkerboarding puts gives the bees the urgency to bridge gaps in the broodnest.  The queen will lay up the empty comb and the bees' sense of a continuous nest will be satisfied. 

One more thought on broodnest continuity...  This is a priority for bees but I have a couple of Pierco frames where one side was only reluctantly drawn out by the bees after considerable time and the queen never lays in that side.  Even when the frame is inserted into the middle of the strongest colony.  Must be some kind of scent...  Otherwise, Pierco frames are very convenient.  

Waldemar

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