This is by far the most interesting part. I was always taught that to get the interference you had to have identical particles -- and I was surprised when I heard this is how we know to treat e.g. two different photons the same, because two different photons in the same location etc. can interfere with each others' probability. But if there is an extremely clear difference between particles that can still generate these patterns, it means things like hidden variable theories have a much better ring to them.