Spec question on textOutline

A question from one of our developers who was asking what is the default color for a textOutline value that specifies two lengths, but no color value.

My reading of the specification text is that in this case the outline color takes the same value as the font color (which if not otherwise specified by the author, is implementation dependent). This seems to us somewhat less than useful in practice, and it might be better if the value in this case were chosen by the implementation so as to create a high level of contrast between the character and its background (e.g. black for a white character on a transparent background).

Not sure if anyone else has run into this? What do people think?

Sean.