I agree with what you said about the contaminants being the biggest problem. You obviously have more real world experience in this area than I do. The point I'm trying to make is that the filter is the component that removes the contaminants. Once the filter is clogged with the "soup", the stuff bypasses the filter and floats around in the suspension. I put on a 1 micron bypass filter on my previous ride. It is amazing how clean the oil looked and tested compared to just the stock filter. It not only trapped solids, but also water and fuel (so it claimed). Being the anal oil changer that I am, I still changed my Mobil1 at 4k intervals. I guess it's just cheap insurance and it gave me something to do:-)
Now, on synthetics. From what I understand from an uncle who worked for a large aircraft engine manufacturer, synthetics are not necessarily better lubricants, but they are capable of holding more particulates in suspension. This was based on their testing as it pertained to piston engines, not turbines so I guess it's sort of applicable. Again, I think the key is in removing (filtering) them.
In any case, change the oil and filter frequently and you'll be safe !
Boy, I hate oil threads :-)