No doubt that there are legitimate arguments for both schools of thought, although the misfolded a-syn aggregation leading to cell death camp is clearly the larger one at this time (neither side having actual proof).

As I said, all of the Alzheimer's research has failed to date. Could be that the drugs just don't work in the cell like they do in cerebral fluid ; could be it attacks the wrong protein ; or it could be that the protein aggregation is just a by-product of the disease and not part of the causal sequence.

Finally, an update!
 

This recent article from AlzForum gives an update on PRX002 (plus discussion and comments).

α-Synuclein Antibody Appears Safe, Reaches Brain | ALZFORUM

This post on the SoPD blog covers the recently-released PRX002 Phase 1b results (and includes a lot of background information).

Prothena: Phase I results published | The Science of Parkinson's

Jeffreyn, the more I read from SoPD the more impressed I am.

Your latest link is a good example. It describes some complex ideas from immunology and protein misfolding in a non-technical way which is clear and accurate (my colleagues and I worked in these fields and published quite a few papers on them).

I hope that the latest work turns out to be helpful to people with PD.