No experimental proof = an unproven theory.
Does the fact that photon detectors have been shown to be unreliable effect the issue?
[0004] Recently, a weakness has been reported in APD systems that they can be put into a “blinded state” where they are incapable of detecting single photons but where they may be manipulated using higher intensity pulses of radiation.
Read more: http://www.faqs.org/patents/app/20120063789#ixzz2NJ4kWJj0