Hello, Martin.  It's as though the HIV changes
its RNA for each host.  Okay, say you divide the
genes into two sets.  One set is made up of the
genes that are "species specific", i.e., they are
the ones that, say, make us "human" instead of
some other species.  The other set are more
"changeable", and account for the more subtle
differences among individuals of a species.

Now, with these two sets in mind, the HIV goes
into a host, invades the bloodstream and begins
to blow out the T4 guardians.  It's as if the HIV,
as it proliferates, takes on an individuality that
is different for each individual it inhabits. While
the HIV's species-specific gene set usually stays
the same (subject to rare random mutation), the
other gene set in the virus is purposefully altered
(as a natural function of the virus) in line with
the DNA of the host.

Maybe it is this individualization, coupled with
the astounding capability of HIV to hide, that
makes the virus so elusive?  (that's assuming
that it actually does exist, as you seem to deny
in your posts)