1. IMHO it's unnecessary to have a own template for this and to be addicted of this.
2. as you see here: http://xenforo.com/community/threads/how-do-you-make-your-own-preview-tool-tip.18383/ it's causing troubles if you forget it
3. if you have >2 add-ons including the tooltip in the same page, you'll have >2 elements with the same id, and AFAIK you shouldn't have more elements on the same page with the same id (i know nothing will change, but... )
why not just create the "tooltip container"
<div id="PreviewTooltip"> <span class="arrow"><span></span></span> <div class="section"> <div class="primaryContent previewContent"> <span class="PreviewContents">Loading...</span> </div> </div> </div>
- the add-on coders don't need to take care of this
- You'll have really only 1 container (and not maybe more with some add-ons)