That works both ways Jane. If someone posted a credible scenario of how Shiela committed the massacre the guilters still wouldn't be open to considering it. Stalemates
There has been no credible scenarios of how Sheila committed the massacre. From the posters who have been kind enough to try.
Mike saying 'by shooting them' or Roch saying 'Sheila shot them but I can't explain Nevill's phone calls', is not enough.
More detailed scenarios have been dismissed. No one believes Nevill rang Bamber & the police after Sheila started shooting the twins or after he had been shot himself.
But feel free to submit you're scenario.