> Has anyone had any experience using a "lock mitre" type of joint for the
> corners of supers?  This joint can be cut in one pass with a router
> table.
 
How best to make the corners is a perennial question, and one that likely
will never be fully answered to everyone's satisfaction.
 
There are two types of corners in common use in North America after many
years of people trying everything imaginable: the finger joint
(beekeepers's 'dovetail' -- not a true dovetail) and the rabbetted corner.
 
I suppose the reasons for these two being accepted widely, with the former
being  considered the more preferable, is ease of manufacture, assembly,
and durability.
 
The 'dovetail' requires more equipment to produce and is generally the
sign of a manufactured box, although some jigs for home building are
available.  The rabbeted box can be made quickly with any good tablesaw.
Assembly in either case is quite simple, with the former style being
self-aligning.
 
Either style can be assembled with or without glue and will have a long
service life (usually) even if dropped repeatedly when full of combs.
 
I have seen other corner styles on boxes made by woodworking enthusiasts,
and although some may be as good as the standard joints, others may be
subject to irreparable damage when dropped.
 
Allen