I remember several John Cockroft designs from Speaker Builder in the 80s and 90s. They were usually meant to use wall reinforcement to boost the bass, and he has been an advocate of a variant of the transmission line, with a short, usually unfolded line, that is very heavily stuffed -- the stuffing is supposed to slow the speed of sound in the line so that it can be shorter. Often the woofer was mass loaded also, as it is in this design.
I do not know how these speakers sound, but I don't believe his views on line stuffing are commonly accepted (doesn't mean he's wrong, but that his view shouldn't be accepted as gospel).
But his advocacy of wall mounting may be part of what makes such speakers sound good (assuming that they do), since being close to walls, floors, or ceilings increases the amount of pressure, hence bass. But the frequencies increased (and also decreased because of cancellation) depend on the distances to all boundaries, so a speaker meant to be placed against the wall and on the floor can have a more predictable bass (re Allisons). The problem is that the higher frequencies will also be affected, and their the interference with the wall may be more detrimental, so often the tweeter is placed facing outward and away from the wall.
