My anecdote of the 'sterile' Maya excavation pit was a poor choice but
it did spark 'significant' discussion.  Judging significance is a
largely arbitrary, delicate matter, while keeping CRM clients (or the
public at large) content with paying archaeologists who may only recover
minimal or 'negative' evidence is also an ongoing challenge.  While
humans are adept at leaving the litter of their existence behind, not
all surfaces of the earth have (yet) been so impacted.  For example,
surface suggestions of human activity at a given site (such as can
scatters) may in fact be the only human impact, or the surface
suggestions present may have been physically shifted by
post-depositional processes.  Evidence also simply disappears with time.
This is where I derived the aspect of research 'gamble': as in making
decisions to undertake large-scale/considerable investigations when one
cannot be certain if the results will validate the expenditure of labor
and other investments.  This is a business-like approach,
perhaps/hopefully less critical to academics than CRM professionals.  In
this it reinforces the value of traditional academic research in that
larger 'gambles' may be feasible: a valuable companion to the increasing
proportion of archaeology conducted within the constraints of the CRM
domain.

Larry Buhr
Dept. of Anthropology
Univ. of Nevada, Reno