To get a row displayed in recordSet browse mode, you have to define a field, you can't really circumvent that and add a field in Module_0.php, body() part.
If you don't want to show this field in view mode, there are 2 ways.
1) enable access callback on this recordSet and for 'view' action disable that column
case 'view': return array('my_field'=>false);
2) define QFfield callback and either do not create any element or create a hidden element.
Hope this helps,
Arek