We work on ArcMap 10.6, and have MXDs using database connections (.sde files) that point to the C:\ of a user that no longer exists (e.g. C:\users\alpha\test.sde) and certainly, that path doesn’t exist on the PC from which the MXD is being loaded, but the MXD loads without error.
We were playing with connection neutral SD files for publishing, with the original MXD pointing to our development database. However, when we publish to our Pre-Production environment, it is still pointing to the Development environment despite no data store existing on the server for that connection. I would expect that publishing to fail or throw an error but it worked fine, how is this possible?