[css-position] Seeking spec clarification on effect of position: sticky on table elements

A recent discussion on a Chromium issue[1] revealed disagreement regarding
the behavior of position: sticky on table elements. The root of the
disagreement is the following wording within the CSS 3 position spec[2] for
position: sticky:

"The effect of position: sticky on table elements is the same as for
position: relative"

The position: relative text is:

"The effect of position: relative on table elements is defined as follows
(emphasis mine):

  * table-row-group, table-header-group, table-footer-group and
table-row *offset
relative to its normal position within the table*. If table-cells span
multiple rows, only the cells originating in the relative positioned row is
offset."

Based on this text, an argument was put forward that for these table
elements position: sticky should offset not relative to its flow root, but
instead relative to its normal position within the table. The basis of this
argument is that the position: sticky spec specifically says the effect is
"the same".

My belief is that position: sticky should apply to table-row-group,
table-header-group, table-footer-group and table-row identically to how it
does for other elements; offset with respect to its flow root.

I note that back in Oct 2014 there was a similar discussion[3] in which an
intention to update the wording was declared - but this seems not to have
happened? (Or the wording was updated but is still unclear!)

Thanks,
Stephen

[1] https://bugs.chromium.org/p/chromium/issues/detail?id=690896#c10
[2] https://www.w3.org/TR/css-position-3/#position-property
[3] https://lists.w3.org/Archives/Public/www-style/2014Oct/0301.html