It makes sense to me that the pattern of blood would leave a hole but several splatters would be around this void. I think that is what Dr Lee meant. I can't even blow smoke rings and I don't think my lungs can do it with blood. I think you have Dr. Lee's explanation confused. A pattern circular in nature, would mean several droplets of blood forming a circular pattern, leaving an empty space like a donut in the middle of the pattern, not each drop of blood. Remember that site it says blood STAYS in droplets and hits the surface. The surface also helps to detrmine the pattern. Hard smooth surfaces like glass would leave spikes around the droplet if it was dripping blood. I can't get a good enough view of the blood on the table to see anything but that it runs.