A previous comment on this blog noted “I still forget that changing something on the template I’m working on changes all the previously made charts.” I promised to address the subject of decoupled panels. I don’t want to call this a “solution” because that would imply that templated panels are a problem! It is really useful to template panels, in the right context (more on that below).
Decoupled panels have their place too. Sometimes you will want to make modifications to a panel which are very specific to one block template, project or well. Not only are you sure that you won’t need the panel elsewhere, you also want to protect it from out-of-context modification in the future.
You could “copy” an existing panel template and work with your copy. You would still need to remember not to modify it later, and it would still be clutter in your panel templates list.
Decoupling is the process of making the copied panel template “local” or “private” to a block template. The panel is no longer associated with its original template; it is not named, it will not appear in the tree and cannot be used in other blocks. If the block template is read-only then this panel cannot be edited. Its settings will be lost if the block template is deleted. Underneath, it’s still using a panel template, but for all practical purposes the panel properties become part of the block template.