1) Update tags (from library) always modifies the file's Modified date. This seems wasteful when nothing has changed.
This forces a tag write, which by definition, modifies the file.
If you leave automatic tag writing enabled (the default, and our recommendation), you would never really need to run this tool manually.
2) Re-enabling UTwFIC does not automatically cause MC to push dirty (eg. updated) database properties out to file tags. This surprises me. I thought it worked by having a last modified time on the database record, and then the background worker would push out dirty tags to files. I can see that someone might want to ignore updates for previous changes unless they manually update. But I can also see that most might want to have previous property modifications to automatically update tags once UTwFIC is enabled.
If you disable tag writing, we don't save that the file should have been tagged but wasn't. The date modified is used to detect external changes. In other words, it's the file system's modified date not the date modified in the library.
