[indutny]

I think photon self-interaction might be thought of as a confirmation of photon's existence. Particle ontology is a tough question, but I don't think there is a reason to exclude photon from the list without excluding all other particles.

[indutny]

Not to mention that experiments suggest that atoms don't play any special role in the underlying physical structure of reality.

[zyxzevn]

Photons can also be seen as waves. And waves can also influence each other, in non-linear situations.

Because the experiments and theory are so simple, I think it is the most scientific approach, to at least test this Loader model more thoroughly. Even if I don't agree with it. ;-)