The name is ok once you know what the flag does. But if you don't know, it's kind of unintuitive. Full name of the property is resource_local_to_scene.
The state of this flags is only relevant if you use instanced scenes and need to mess with the resource itself (e.g. animating shaders). Which may never be the case in a typical game/workflow when you just use pre-made resources. More likely to be needed if project is inclined towards procedural geometry and animation. My projects typically gravitate to that so I stumbled upon this early.
Since this property is tied with instancing, it'd be better if the word instance appeared in the name , rather than just scene. Maybe something like resource_unique_in_scene_instance or resource_local_to_scene_instance. But perhaps this is not succinct enough. The tooltip gives decent description of what it does though.
As for docs, I tried to search up a bit, and the only explanation of this property appears in the Resource class reference. It's only a single sentence identical to gui tooltip. Introductory section that explains the concept of scene instancing is just an overview that doesn't go into details of resource handling.
A short section named Resources and scene instancing could probably find its way into docs. Maybe some place under Getting Started / Step by Step / Resources / Nodes and resources.
