1st col. & row 2nd col. thead 3rd col. 4th col. 5th col.
2nd row thead abcd abcd abcd
5th row tfoot a b c
3rd row tbody abc abc abc
4th row tbody ab ab ab

The vertical distance between any 2 contiguous rows should be the same at all times.

Related testcases from CSS 2.1 test suite:

The vertical distance between the cells in nth row and the cells in n+1th row (or the cells in n-1th row) should be the same regardless of the selected value in the <select>.

Border-spacing should be unique around cells, should apply only once. Border-spacing should apply to table elements, and not to table-row-groups. The vertical border-spacing between 2 cells of 2 table-row-groups should merge together.

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