The end style syntax - (%%) - does not behave as expected when it's cancelling a style that was applied at the start of a table cell, before any text within that cell.
Additionally, when using this problematic markup in CKEditor, the unrespected (%%) gets silently dropped from the source. (Tested in CKEditor 1.10 on XWiki 8.4.2.)
The CKEditor-specific problem is a particular issue for our non-technical users because they expect to be able to select the first word(s) inside a table cell and apply text coloring, etc. to them – which CKEditor happily does apply to those words only. And CKEditor does properly preserve the (%%) chars when switching to/from its Source view. However, upon subsequently saving the page, the (%%) marker is lost.