It's seemed to me from the beginning of this thread that there are three possibilities. It may be late to write this now -- I intended to post it when the discussion began -- but here goes.
1) It's an object that is periodically uncovered and covered, like the Maid of Harlech. This could be part of the Electra. The evidence against this is that metal detectors -- and visual search -- in that area did not detect it.
2) The area where it is seen occasionally captures elongated objects (perhaps logs) for a time, but does not retain them. The question is whether there is a source of such objects to land in the water and be moved into that place and then elsewhere by natural forces. It seems that People Who Have Been There have been answering that question.
3) It's an optical illusion, which Ric thought it was initially, and which seems the likeliest explanation, given that nearly all such sightings are exactly that. The evidence against is that occasionally some have been determined have a high probability to be real, not illusory objects. An example is the Bevington Object, now considered to have a high probability of being a landing gear assembly from the Electra. There are others also considered to have a probability to be other than illusory.
Don