System i Navigator visual explain HOWTO?

I'm looking for a detailed description of what all the nice graphics
mean on Visual Explain. I'm trying to understand a series of complex
SQL statements in terms of performance characteristics, and I'm pretty
much overwhelmed by all the little boxes.

I Searched The Fine Web, and although there is stuff out there for V5R2,
I'm not sure that's particularly applicable to V5R4. If it is, I'll
just go hunting down all the old articles I skipped over because we
didn't use SQL then :-)

I searched 'our' wiki (wiki.midrange.com) as well as the new IBM wiki
(http://www.ibm.com/developerworks/wikis/display/WikiPtype/IBM+i) which
at this embryonic moment is just a link dump. The Navigator home page
http://www-03.ibm.com/systems/i/software/navigator/gettingstarted.html
has a bunch of stuff from 2005 as well as some broken links to articles
that I can probably find in print faster than on the web.

The help included with Navigator was not very helpful.

Strangely enough, I might just spin through the suggested keys in files
QQIDXA, QQIDXK and QQIDXD as suggested by
http://publib.boulder.ibm.com/infocenter/iseries/v5r4/topic/rzajq/idxadvisor.htm
and build the suggested indexes from that and just not worry about the
visual aids.

--buck