Overall, I have to applaud Cort's approach in presenting this, I wouldn't have known how to make this coherent, since we have people talking at cross purposes.
I also have to confess my own health has made me cranky in the past few weeks, making objectivity and concentration more difficult. If people on the forum have noticed, I hope they will grant me some leeway.
More and more, it seems I am hearing "if this were a virus causing a disease, it would behave in the particular manner I expect." Past success in discovering infectious agents are presented as classic models. Unfortunately, the low-hanging fruit of infectious disease has been harvested. What remains, of necessity, will be more difficult to grasp.
The 'different virus' pitch is another example of failure to understand research claims actually made. Two virus isolates from the study published in Science were completely sequenced. The Lo/Alter study completely sequenced their amplicons, but never completely sequenced the viral genome. We don't yet know if the blind men have found two separate animals, or the trunk and tail of one.
Arguments that the virus should not show substantial sequence variation are downright baffling. What is the basis for this assumption? The WPI group were able to find two essentially identical genomes. This says nothing firm about what else was present.
Those arguments about copy numbers seem completely at odds. This is a problem I had trouble addressing in reading any of the present publications. Without more work, I am unwilling to take any stated numbers as more than an author's opinion. We definitely find opinions at odds on this subject.
We have had many pronouncements about how science ought to be done in the course of the debate over XMRV. My view may be a minority position.
The textbook cardboard of scientific discovery is a kind of Horatio Alger fable, "He knew he was right, and he stuck to his guns despite the forces arrayed against him." Unfortunately, you can find many more people who always knew they were right in mental institutions than on the stage in Stockholm.
For me the interesting stories are about people who started out dead wrong and learned from nature despite false preconceptions. Science doesn't advance by avoiding all mistakes, but by learning from those people have made. Lessons of the "don't advocate retroviral theories" variety have not led to great advances.
Good research branches out in many directions, even if based on false assumptions. Bad research goes nowhere. I have my own opinions about what we are seeing played out in front of us.
If one guess about mistaken assumptions is correct, we even have a dramatic personal tragedy here. Dr. Weiss, to mention only a single name, may have allowed a Nobel prize to slip through his fingers more than once.