Hello Allen and All,

I will add my opinion. 

> the queen still in the cage,  running around and around. (with candy gone) 

I find this situation every once in a while but not a common occurance.

> 
> Obviously she is free to go, but why is she in the cage?
> Has she left and returned?

 My opinion is she has not left. The bees are feeding and caring for her but only an opinion. I base my opnion on the way she acts when I release her as if to say. Sure glad to be out of the cage. I have seen many queens go right to egg laying and I have NEVER seen a queen balled which was found still in the cage with candy gone and workers coming and going. 
 
> Is it only by chance that we see her there on a brief visit back to her old
> home?

I think we are putting human charactoristics on an insect here. 

> Or is she just to stupid to leave?

I would not call finding the queen in a cage with the candy gone unusual or rare  if we are checking within 10 days.  I believe most queens would come out of the cage in time but I always am back checking the cage in 5-6 days at the longest so really do not know about finding her after a longer period. 

I would not say stupid but would say something happened which caused the queen to be leary of passing through the hole. Queen afraid to pass through the opening is the problem as I NEVER see the queen coming and going but only as Allen said "queen going around in circles and failing to exit through the hole".

 Perhaps a worker tried to ball the queen in the passage and she has become leary of passing through the hole because of the experience?

 I have tried for the sake of experimentation to push the reluctant queen through the hole in the cage but to no avail. I always have to remove the screen to release her.
By taking a straw and trying to herd her through the hole she seems to avoid the hole at all costs. I admit I have pondered the same scenario as Allen.

Sincerely,
Bob Harrison