I don't see why that would happen. If it's working at one point in the template, it should show up everywhere. Are you sure it's not inside a condition that's not true, or maybe not being displayed for some other reason?
Another possibility is that you have something like
Code:
<vb:if condition="$post[title] = ''">
somehwere in the template, which would most likely be a mistake (because of the single '=').