Dear David,
>> I would appreciate hearing peoples' views on whether mental (and/or
astral) travelling, as described by Bardon and other authors, and lucid
dreaming are one and the same, or at least, variations on a single basic
mechanism - this is a question which never seems (at least to me) to get
answered satisfactorily; rather, it seems either to get misinterpreted,
or (deliberately or otherwise) glossed over, at least, publicly. <<
I suggest --
http://www.ABardonCompanion.com/Dreams.html
http://www.ABardonCompanion.com/IIH-Step9.html