Steve wrote:
[...]
I think it's useful to use the words "lean" and "edge/heel"
(kayaks edge, open boats heel) separately.

Heeling is used for all kind of boats,
edging is mostly used for kayaks and closed canoes,
and leaning is mostly for open canoes, also because
the action of leaning is more a kneeling thing, I suppose,
but it also depends on the language one uses:

american english(?): boat lean - body lean
american english: J-lean - bell-buoy lean
english: edging - leaning

See this picture too:
http://www.xs4all.nl/~dbarends/lln.gif

Personally I prefer to use the word 'leaning', because it is easier
to understand what is meant by leaning (to the) right or left,
where edging (to the) left or right gives more room for misinterpretations...
as I have noticed.
Also, in the Netherlands at least, edging right is leaning left, and vice versa,
and that makes it even less desirable to use those words together indeed
to avoid confusion!
Luckily the boats and the water don't care about it at all,
and only know a right or wrong way to do it ;-)

Other interesting article to read about leaning:
http://www.paddlermagazine.com/issues/1999_2/Skheel.htm

Dirk Barends