The documentation of ElementTree mentions "path" in describing the
arguments to certain methods. However, "path" is never defined. I
realize that a "path" is (at least a partial implementation of) an
XPath, but there's nothing in the documentation to suggest that to
someone who is not aware of XPath. I also realize that there is a
reference to the external ElementTree documentation, and that
ElementTree support for XPath is documented there. I think "path" should
at least be clarified with a reference that says something like "As used
here the term 'path' refers to ElementTree's support for the XML Path
Language (XPath); see
see http://effbot.org/zone/element-xpath.htm fordetails"

Next, a swarm of nits:

The documentation of the Element methods find, findall, and findtext say
that their arguments can be a tag name or path. (Using the same wording,
which makes it strange that the argument to findtext is called
"condition" while the argument to the other two methods are called
"match". I'm sure there's something important about this distinction,
but I can't figure it out from the documentation.

The documentation of the corresponding methods of ElementTree call the
arguments "path", rather than "tag" or "condition". The real problem is
that these methods are documented with respect to the element(s) "with
the given tag". [The "the" is missing from the documentation of
ElementTree.find and findall.] The documentation says these methods are
the same as calling the corresponding method on getroot(), but whereas
the Element methods refer to tag name or path, the ElementTree methods,
although they call their arguments "path", only mention tag names.
Finally, the ElementTree methods say "path is the [top-level] element to
look for", which, it seems to me, is redundant given the first sentence
of each of each method's documentation.

I agree. I found the documentation very difficult to understand.  The term "top-level" can be confusing. Consider instead something like "search the entire tree".

A few other comments about the documentation of findtext:

findtext(path[, default])
    ... Returns the text content of the first matching element, or the default value no element was found...

The first comma (,) following 'element' is unnecessary and in fact incorrect. Also, 'if' is missing. Sentence should read "Returns the text content of the first matching element or the default value if no element was found."

findtext(path[, default])
    ... Note that if the element has is found, but has no text content, this method returns an empty string.

Again, an unnecessary comma exist and there's an extra word. Should read, "Note that if the element is found but has no text content, this method returns an empty string."

Note, the wording changes should be made. The other suggestions should be considered soft suggestions and merely my preference.

As per PEP 257, “Returns” should become “Return” (it’s a command, not a description).

I think you are incorrect about the comma after element.  Without the comma 'the first matching element or the default value' are tightly bound, meaning that if either of those is true, then the default value is returned.  That's obviously incorrect, so a human will parse the sentence the way you expect.  But I think technically the comma after element turns the sentence into two independent clauses conjoined by 'or', so that either the first matching element is returned, or the default is returned (if no element was found).  I think it also reads better rhythmically (you will note that I used a comma in my sentence, as well, even though in that case no technical ambiguity results from leaving it out).

The comma in the other sentence I think is optional, and I agree that it reads better without it.

> As per PEP 257, “Returns” should become “Return” (it’s a command, not a description).

Upstream ET uses JavaDoc conventions, where the conventions are
designed by technical writers, not hackers.  In JavaDoc, descriptions
are 3rd person declarative (after all, the documentation describes
what the function does, not what you want it to do).

http://java.sun.com/j2se/javadoc/writingdoccomments/

The incompatibilities with Python's NIH-standards are unfortunate, but
that's the way it is.

The missing/extra words in the findtext description is just a case of sloppy copy-editing, most likely after a quick reformatting.  Not sure why you're spending all this energy arguing about commas, though.

Documentation patch accepted, for the "path == XPath" confusion and clarify other points too.
http://bugs.python.org/issue6488#msg90528

See also patch attached to #2864 which proposes to add an XPath example to the documentation.