pghackers discussion of 5-Jan-2000. The amopselect and amopnpages
estimators are gone, and in their place is a per-AM amcostestimate
procedure (linked to from pg_am, not pg_amop).
lisp.sgml is a placeholder for Eric Marsden's upcoming contribution.
catalogs.sgml is not yet marked up or integrated.
It should perhaps become an appendix.