So I've looked through the literature and I found a review article saying all of this and more. It was written by a group of respected physicians from American and French hospitals and it clearly supported the widely held belief that you should drink two to three litres of water a day.
This is a common occurrence to have your brood chamber become honey bound during the main nectar flow. A typical hive body will have a brood cluster in the middle and the outside frames will contain honey. A honey bound hive happens when brood begins to emerge, it is replaced with nectar.
Provided the bees have sufficient food stores for winter in the hive, the bees should not be disturbed. Opening the hive during the cold season and inspecting frames for food is definitely not an option. Instead, simply lift the hive on one end for a weight check. A single box 8-frame hive should contain a minimum of five frames of honey; with an average net weight of 2.4 kg per frame this totals to 12 kg of honey.