Correct me if I am wrong, but if a contact already has checkboxes selected, you cannot select a new checkbox in the field in a mass edit. It will overwrite the other checkboxes and leave the contact with one box checked. This is the same behavior for text fields, rather than adding to the text that’s there, it is replaced. The benefit of tags is that they are not replaced but added to - or at least I think that’s why you should consider them. At this point, I have to create new custom fields for any and every type of grouping or a list. It creates a lot of clutter. It would be much simpler to tag and then sort/create a segment by an exact match tag.