So why use touching top bars in the Layens hive. I know Leo Sharaskin states it helps retain heat and minimizes disturbance during inspections. When using open top bars and a cover cloth I see less disturbance during inspections. All you do is peel back the cloth and peek down in maybe a few bee come up to see what is going on. With the touching top bars you crack the propolis seal and the bees "go wild". The open top bars also give you many other options for you hive, like being able to emergency feed in the winter, or using in a vertical style hive. Even Layens himself used the open top bars in his hives.