There are three options for removing elements in the current document:
The first two apply only to templates; the third applies only to records.
Its important to note that there is no way to undo any of these three options: ie. you cannot apply a 'Remove' option to a document in RIMMF and then revert the document to its previous state; you would have to close the document and re-open it (to the last saved version).
The last option–Remove Empty Elements–is actually a routine that RIMMF uses itself whenever you save a record. Since records are typically created from templates, and elements in a templte are not always completed in all cases, the program automatically strips out these empty elements when you press Save in a record.
The other two 'Remove' options apply to templates.
When designing a template, it might be useful to quickly strip out all elements that are not officially defined in the Toolkit. Use the first 'Remove' option to achieve this.
In addition, it might be useful to remove 'Relationship' elements (though to be honest, we are not sure why!). Use the second 'Remove' option to achieve this objective.
Applying the first two options, sorting the result on RDA Rule number, and collapsing all of the second-level elements except for 'Preferred title', would result in the following, failry concise, template for a work: