A similar BugMonkey script that achieves the "link on the bugview page" part:
$("div.changes:contains(ase)").each(function(){
$(this).html(
$.map($(this).html().split(/<br.*?>/), function(sLine) {
return /^((Added|Removed|Created) subcases?|Parent changed)/.test(sLine) ?
sLine.replace(
/(subcase |case |)(\d+)/gi,
'<a href="?$2" onmouseover="b1($2,this)">$1$2</a>') :
sLine;
}).join("<br />")
);
});
... it also handles the case where you've added/removed multiple subcases, and also provides a link when you change the parent case. (It also shows the case info popup when you hover over the subcase link)