If these measurements are correct, and knowing how careful Dr. Hickey is, and understanding that the centrifuge and analytical technique will determine vitamin C accurately - in a liposome or not - then it would appear that we have learned something. That up to 5 grams, at least in these individuals, ordinary vitamin C is all absorbed. Occam's razor. It gets almost silly coming up with some other explanation.
Both Cathcart and Pauling felt that a great deal of vitamin C was lost during digestion.
Pauling on a Cancer Video (lecture) said his own experiments had determined a "50% loss", but the dosage wasn't given, and we know that Pauling consumed 18,000 mg.
Cathcart felt only 20% made it to the blood stream (or tissues?) intact (He said this during his video lecture on bowel tolerance). I have felt that Cathcart's guess was probably low, because he based it on the equivalences of oral and IV clinical effectiveness. He felt that ascorbic acid was "twice as powerful" as sodium ascorbate, but since there was an 80% loss, IV sodium ascorbate was twice as effective. (This is all from memory - which I no longer trust. It is recorded on the video.)
Are we back at square one? What if... What if DHA is also being measured in the Hickey experiments? The semi-oxidized form of ascorbate? Any chemist want to hazard a guess? This may explain why the quantities in the blood are equivalent, but why Pauling/Cathcart felt there was a loss - less of the reduced ascorbate? So they could all be right - to some degree.
Hickey's book mentions one study of men that showed only minimal absorption as the dosages were increased. Page 45 (Vitamin C: The Real Story) and this studyhttp://www.ncbi.nlm.nih.gov/pubmed/?term=On+the+absorption+of+Ascorbic+acid+in+man++Kallner%2C+A.+I. and another in women that Levin or the NIH used to set the RDA.
Then Hickey goes on
The NIH suggested the body was "saturated" at an intake of 200 mg per day. According to this notion, increasing the dose would not sustain blood levels at a higher value than 60-70 uM/L and the majority of larger doses is not absorbed from the gut. This is clearly an error, as sustained blood levels of at least three times this claimed maximum concentration are achievable with repeated oral doses.
What these data (5 g/5 g) seem to suggest is that the power of liposomal is not related to the absorption from the gut into the blood stream, but rather as Dr. Levy's research supports, from the blood or "extra cellular fluid" into the cell and perhaps on into the sub structures (nucleus, mitochondria, etc.) (Dr Levy shared slides from a recent talk in Algeria - where he was treated well, " like a King. "Might be exaggerating.. Conversation was a while back. He was cheered and did feel good about the trip..)
Rereading Hickey's paper http://184.108.40.206/files/Pharmacokinetics%20of%20oral%20vitamin%20C.pdf I noticed (among other things, Riordan's Hunningshake was able to increase his own blood concentration from 200 uM/L to over 300 by adding liposomal) that the figure 1 - the 5 grams were of one person, a woman, and were "doses" these charts are of repeated dosing? I couldn't find the complete explanation in the text.