Text Mode Display Name Help

Hello! Still new to text mode so kinda feel dumb asking but here goes. 

I don’t want my grouping to have display names. When I remove the displayname line completely, it defaults to be grouped by the field name. If I leave it blank at the end like - “group.0.displayname=” it’s still pulling the field name. According to the tip in this article (¾ way down the page), if I leave it “blank”, it should just be grouped by the value but it seems to not be working so I must be doing something wrong. Thanks in advance :) 

https://experienceleague.adobe.com/en/docs/workfront/using/reporting/reports/custom-view-samples/grouping-rename-grouping