I never thought of that. Does it help in any way? Personally (old school) I allways had an upper entrance (vent hole.
Thank you for asking.
I think an upper entrance above the brood chamber can be good for many reasons. Ventilation, an entry point above the brood, an entrance above an excluder, and others positive benefits.
I however do not like a top entrance because of the loss of trapped beneficial heat, the loss of using a shim for re-queening, feeding, or anything else without shutting off the top entrance, dealing with guard bees from this entrance, etc.
Studies have clearly shown that bees prefer a lower entrance. Bees naturally will not select a top entrance if they have a choice. I think this is by design from issues with heat loss, possibly rain/water issues, etc.
I think that an upper entrance can be very beneficial to the enlarged cavities (unnatural) we provide bees and some good can be achieved from the use. But I feel no additional benefit can be gained by a top entrance. You can gain good benefits with an upper entrance. Beyond that, by going all the way to the top, you now lose benefits.
That is why I always point out that an upper entrance and a top entrance, are two different things.