I think I've narrowed down my problem space a bit.
Playing with various "fast" versus "slow" queries leads me to ask:
GIVEN:
15,000 reocrds with a 'text' field named 'text'
Average 'text' length about 10 K.
Full text search using lower() and LIKE and even ~* sometimes on that
field with a keyword.
What can be done to maximize performance on such large chunks of text?
More RAM?
Tweak that 512 number in postmaster.conf?
Faster CPU?
Is my only option to resort to a concordance?