Explanation of question
The following table illustrates the issue:
HTML source for table:
<table> <thead><th>Column 1</th><th>Column 2</th><th>Column 3</th></thead> <tr><td>Type 1</td><td rowspan="2">Common Info</td><td>Info 1</td></tr> <tr><td>Type 2</td><td>Info 2</td></tr> </table>
You'll notice that it isn't clear that the non-header cells in the first column map to their corresponding cells in the third column, because of the cell merging. In my opinion, for conventional information tables formatted in this way, such cell correspondence exists, but the above presentation method doesn't do a good job of indicating this.
A possibly good way to present...
If I could mark-up the following table design using HTML, such that the cell entries were not images, then I believe such mark-up would yield a good way to present such information:
Unfortunately, I didn't use HTML to create the above design—I just used a simple raster graphics editor (Windows Paint) to create it.