Going ahead with the switch to tabs. This is a major coding standards change! If any unusual parser bugs show up, check this changeset. Converted all .php, .js, .tpl, .css, and .json files and did basic testing.

.mcePageBreak {display:block;border:0;width:100%;height:12px;border-top:1px dotted #ccc;margin-top:15px;background:#fff url(../img/pagebreak.gif) no-repeat center top;}