Excel 2003 has a feature that I use and like; using the text at the
head of a column of data to refer to it.

I use that extensively in in-cell formulae.

However, it seems not to work in "in-chart" formulae.

That is, I've used my best guess for the relevant syntax (=Worksheet!
Label) for series values when creating a chart and it doesn't work.
I've also tried a few variations on the theme.

Has anyone done this successfully?
Does anyone know for a fact that it doesn't work? If so, how did you
come to the conclusion?

It is frustratingly close to being an immensely useful tool - no more
dynamically named ranges for charting!