Good points and good information there Mr. Wilson. I agree that the best skimmer design is based on recirculating counter current but of course it is a simple option and not a requirement (just like everything else). Recirculating skimmers, on average, cost double and not everyone should consider modifying there skimmers, this is not a simple modification for most. Drilling the expensive acrylic body can often result in fracture and voided warranty.
I wouldn't personally ever setup a skimmer to be fed by a siphon over a pump, in theory the perfect siphon will deliver consistent flow but in practice it's not the case and if flow is suddenly increased a big mess will exist. But that doesn't mean it can't be done, I simply don't see the benefit and wouldn't recomend it, however everyone's thoughts are different.
Moving a lot of flow through the sump has many benefits, of course so does moving little flow. It's important to remember it's not a simple science and there are many ways to skin a cat. I won't go into too much of my reasoning again but I will say real experience and evidence trumps theory. I believe that the best resource for this can be found in the RC site where every month some of the worlds best tanks are showcased and described. There you will find almost all tanks showcased run return flows around 5-10x display volume, if not more. For me it's hard to argue with success, they got to be doing something right.
You're obviously a smart guy and you have experience in aquarium design but we definitely have some differences in opinion and what we consider simple, which of course is a good thing
I also noticed you're new to this site (WELCOME BTW
), perhaps you could provide a link to your tank(s) or some of the work you've done. I always like to see the work of others who offer different approaches.