I struggle a bit to understand the documentation here: http://w3c.github.io/html-reference/terminology.html#transparent which is linked to from here: http://w3c.github.io/html-reference/a.html#a-changes
As far as I understand it the following code should be ok:
<li>My list item is wrapped in an anchor.
First of all, you are not using a HTML specification. http://w3c.github.io/html-reference/ is just a "non-normative reference", and outdated (it’s a draft from 2012).
The HTML5 specification (which is currently the latest HTML W3C Recommendation) is https://www.w3.org/TR/2014/REC-html5-20141028/. HTML 5.1 is currently a Candidate Recommendation (it will likely be a W3C Recommendation soon).
The following links point to the HTML5 W3C Recommendation.
The content model of the
a element is transparent. The content model explains what other elements the
a element may contain. In the case of transparent, it means that the parent element’s content model will be used. But the content model says nothing about where the
a element may appear.¹
The "contexts in which this element can be used"² lists where the element may appear. In the case of
Where phrasing content is expected.
So you can use
a wherever you would also be allowed to use text,
span etc. Note that the
li element is not listed here (
li is not phrasing content).
See the content model of the
ul element: it only allows
li and "script-supporting" elements (not
¹ Except for
a elements nested in an
a element, of course. But this is explicitly not allowed: "there must be no interactive content descendant".
² This listing is non-normative (only provided for convenience). You can see the normative contexts by checking each possible parent’s content model.