Just to reiterate - i developed the DLD hive to suit my own beekeeping on the roof of a 5-storey house. It derived from pushing two Deep National together, back to back, and then removing the two back sides to make one long box divisible with a divider board. Saves having to have a spare hive/nuc hive for every National. It works for me , so after ten years I published ‘New Beekeeping as a new presentation of old principles. Northern Bee Books publish and I don’t ask for any royalties - it is just a contribution to the literature of beekeeping - for those whose minds are open to progress.
The other point is that the DLD is designed to be made at home from ply and softwood battens along the top - and for the attached legs. ‘Construction Information for Dartington hives’ is also published by NBB, with layouts to show how the pieces can be cut from the ply sheets - you just take the diagrams to a local builders mercant and get all cut to accuracy. Then you assemble at home using a pair of window clamps. So it is minimum cost, for those for whom that is important.
This forum shows there are many who are just not interested in the possibility that a 100 year old hive design might be improved for our changed modern conditions - but there are some. If beekeeping does move forward, they will not be part - no matter.
I will continue to offer information, as clearly described as I can, as I suspect the problem is that, while some people can visualise in three dimensions what words mean, others lack that ability - they just cannot see it - so they feel they must attack to justify their inabilty to join the discussion.
Last word - although designed for home manufacture - I was an engineer so like to make my own - the DLD. Hive was available for some years in kit form from Stamfordham Ltd, until the workshop in Lithuania closed down. Thorne's sold it made-up for a bit but that was expensive of course. There is an opportunity dor some other hive maker to offer it - I would welcome and help publicity. Omlet adopted the principles for their beehaus and gave me 8 DLDls for use of my copyright on the management info they put on line.
I have been given 9 ‘well loved’ DLD’s from aged beekeepers that I hope to offer as ‘loan hives’ after renovation, if anyone wants to find out for themselves if it is easier for them to operate, especially over swarm control.