I think 23 out of 31 have gone now - with the best will in the world you can't carry on as leader if (almost) everyone you work with thinks you are useless.
If nothing else at all, if [MENTION=1416]Ernest[/MENTION] is correct that all these treacherous MPs are to blame, then it indicates that Corbyn is a dreadful judge of character, choosing all these people to support him.
Beyond that, just how strong can this shadow cabinet be, given it's, at best, a B-Team now?