I know I’m late to the party on this one but it’s something near and dear to my heart since any CMS I work on or consider for a project has this as a feature. Some thoughts:
- sounds like it’s been decided to make this a plugin, I would strongly encourage it as a core feature, it is a bullet point on any major mid-size CMS
- was a method determined for editing "invisible" elements? Not just those that may be in the HEAD like META tags but things such as hidden/background images or text that would not be displayed anywhere. One way of handling this is having a tag and associated text to block out these elements. Not having seen this feature working in MODx I don’t know what is used to denote an editable piece of content on the front end, I will use a pencil for exampe. So you have your [*backgroundimage*] TV that gets exposed to the front end and at the top of the template you might have:
[*START front end block*]
[*backgroundimage:edit*]
<strong>CLICK TO EDIT the background image</strong>
[*END front end block*]
This only appears when the user is in front end editing mode. I hope you get the idea, it is great because you can stuff all kinds of useful info for non-technical editors in there. I hope I’m not too late to the discussion