You could custom format cell the header row, edit the text color, and set it to 100% transparency. The header row would still be there, but it wouldn't show anything. Not ideal, I guess.
Screen-background-colored text box overlaying the header row?
I feel like I'm missing something obvious, some "just checkmark this option".
In QlikView it was all about work-arounds so John's suggestion will only apply to QlikView.
QlikSense? Maybe by using Dual() and blank characters like 1=' ', 2=' ', 3=' ', 4=' ' etc.. then showing text value instead of number. I
have not tested it yet but i have got a feeling that QlikSense may trim them, so it can be back to square one!
Anyway - hope this helps