> Some folks around here who have made the switch to mediums-only have told
> me they like the resulting arrangement much better.
 
Smaller frames are well suited to smaller people and those who do
not plan to run large numbers of hives.  When I consider the fact that my
wife is less than half my size, it is no wonder that there are those who
advocate different sized and shaped frames.
 
We had several thousand mediums for the past few years, but we have just
sold the last of them this year, since I couldn't justify the extra
handling they require.  FWIW, though, the buyers were commercial
beekeepers.
 
I also know that there is a commercial outfit -- 1000 hives plus -- for
sale in the Peace country (land of HUGE crops) that uses mediums for both
brood and supers.  Joe has been successful for many years and is retiring,
but I imagine he would do it the same again.
 
> A few decades ago Dr. C. L. Farrar favored a mediums-only system, using
> 3-5 boxes for the brood nest,
 
Yes, I custom built 100+ of those hives in the early seventies and
eventually sold them.  They were nice, but did not make any more honey or
winter any better than standards.
 
> Could anyone comment on the burr-combing problem?  Even with full-depth
> multiple brood-chambers, it seems the bees prefer to "connect up" the
> combs in the space between the stories.  Not sure if this is a natural
> predisposition or more the result of an improper bee-space...
 
IMO, bee space is less of a principle than a trick we play on bees.  Bees
prefer on long comb and bee space delays their joining all combs together,
but only delays it.  See also my recent post about how frames do not
necessarily hang one over the other as directly as we imagine --
this resulting in variable spacing.
 
Allen