I've just posted a new issue in the tracker CONTRIB-3299, with a possible fix, but I'd like a sanity check from some-one else please.
If you configure a questionnaire with the "students can view responses" control set to something other than "never", and give students the "readallresponses" capability, students still cannot view responses. You have to give them the "readallresponsesanytime" capability which would be a bit dangerous to assign at a site level. Our course managers are currently assigning it as an override for each questionnaire, which is a bit annoying for them.
Is any-one else experiencing this? Or do most people not open their survey responses?