Group by Predefined Choice field in pivot reports

When you create a pivot report and put a predefined choice field as a row or column, it does not group results like it does for tags. This is annoying for several reasons. 

1. Predefined choice fields force a single value while you can not do so with the tag field types. 

2. Related to the first issue, when you select a tag when adding data, a drop down for a second tag automatically pops ups. This may seem trivial, but actually is very disruptive when you are trying to add a bunch of data quickly. 

3. Tags are very ugly in reports can an clash with other formatting options. While thy don't always show in tag format when used as a row in the pivot reports, you may want to use the value in other reports.