I would suggest removing them totally. To do this you need to make a small change to one of forum templates. In this case the template spHead.php which can be found in the /templates folder of the SP theme you are using. You can edit this with our theme editor admin panel.
Find the display function that displays the breadcrumbs. This is called sp_BreadCrumbs().
Simply remove the line for that function -= or comment it out (put a hash – # – at the start of the line of code.
Of course – as always we recommend that you create your own SP theme so that any customisation is not lost during a future update. (http://codex.simple-press.com/codex/themes/theme-basics/creating-a-theme/). This only takes a few minutes…