JOSM to "Replace Geometry" "The way to be replaced cannot have any ...

Every so often, when using JOSM to “Replace Geometry” so that I can preserve the history of a way, I get this error popping up.
“The way to be replaced cannot have any nodes with properties or relation members unless they belong to both ways”
I also wonder if my method is incorrect.

For example:
I see a large polygon or relation like a national park that is incorrectly shaped. I have a polygon or relation with the correct mapping which I have loaded in a separate layer. I then decide to merge the correct one/s into the data layer. Then, in the data layer, I select one of the polygons that is to replaced and one of the new correct polygons and select “Replace Geometry” and error message comes up.

I assume that one or more of the nodes around the ‘to be replaced’ polygon has one of it’s nodes being used for a gate or similar and a merge would incorrectly shift that item, or that some of the nodes of the way are merged with nodes of another way.
Do I need to move around the polygon and move such items to their own separate node before the replacement, and is it ok to select the ‘to be replaced’ polygon and then Tools>Unglue Ways before doing the replacement.

It would help if Josm or plugins were able to highlight the individual nodes or ways that trigger the error message.

After expressing the above and doing those checks, I find the problem is solved.
…very cathartic :slight_smile: