Both authors clearly stat in these papers and in many others that they have written that they use CO2 as a major driver of climate.
Luthi even uses GCMs

“I don’t think there is clear-cut CO2/temperature correlation in either of these 2 sources. Generally you can’t be seriously suggesting there is a historical CO2/temperature correlation?”
Huge strawman, as it has been xplained manytimes by me and others that you can’t expect one over geological time.

Stop misrepresenting people’s results.

Luthi; You need to read more than the abstract; p2; “It was suggested earlier that there is a strong stationary relationship between Antarctic temperature and CO2. But our data reveal a significant devaiation from this behaviour.” They go to say this is a robust feature and not a measurement artifact; they go to look at AIM and Dansgaard-Oeschger events and a regional effect may slew the records. I don’t think there is clear-cut CO2/temperature correlation in either of these 2 sources. Generally you can’t be seriously suggesting there is a historical CO2/temperature correlation? Here are a couple more graphs while you are composing your thoughts;

http:www.nytimes.com/imagepages/2006/11/06/science/earth/20061107_CO2_GRAPHIC.html

http://www.ferdinand-engelbeen.be/klimaat/eemian.html

Luthi
“From previously published data1, 2, 3, 4, 5, 6, 7, 8 and the present work, we find that atmospheric carbon dioxide is strongly correlated with Antarctic temperature throughout eight glacial cycles but with significantly lower concentrations between 650,000 and 750,000 yr before present. Carbon dioxide levels are below 180 parts per million by volume (p.p.m.v.) for a period of 3,000 yr during Marine Isotope Stage 16, possibly reflecting more pronounced oceanic carbon storage. We report the lowest carbon dioxide concentration measured in an ice core, which extends the pre-industrial range of carbon dioxide concentrations during the late Quaternary by about 10 p.p.m.v. to 172–300 p.p.m.v.”

Berner
“On time scales of tens of millions of years, climate is known to undergo massive changes. Previous evidence has suggested a link between natural atmospheric CO2 variability and these long-term climatic oscillations, but some recent studies have found discrepancies. In their Perspective, Crowley and Berner assess the evidence. They conclude that the CO2 model is valid for high-latitude glaciations but that for low latitudes, altered tectonic settings and problems with interpreting climate indicators complicate the picture.”

“The first-order agreement between the CO2 record and continental glaciation
continues to support the conclusion that CO2 has played an important role in longterm
climate change. The Veizer et al. data, if correct, could be considered a
Phanerozoic extension of a possible dilemma long known for the early and mid-
Cenozoic.”

“Understanding the link between the greenhouse gas carbon dioxide (CO2) and Earth’s temperature underpins much of paleoclimatology and our predictions of future global warming. Here, we use the inverse relationship between leaf stomatal indices and the partial pressure of CO2 in modern Ginkgo biloba and Metasequoia glyptostroboides to develop a CO2 reconstruction based on fossil Ginkgo and Metasequoia cuticles for the middle Paleocene to early Eocene and middle Miocene. Our reconstruction indicates that CO2 remained between 300 and 450 parts per million by volume for these intervals with the exception of a single high estimate near the Paleocene/Eocene boundary. These results suggest that factors in addition to CO2 are required to explain these past intervals of global warmth.”

Both authors fully support the notion of the Greenhouse Effect and CO2’s role in paleoclimate.

Dana L. Royer, Robert A Berner, David J, Beerling; Phanerozoic atmosphere CO2 change: evaluating geochemical and paleobiological approaches. Earth-Science Reviews vol 54, Issue 4, August 2001, pp 349-392

As to Luthi, here is the link; how am I wrong?

http://www.nature.com/nature/journal/v453/n7193/full/nature06949.html

Nt you don’t know anything about economics so stop pretending you do as you will come out sounding sillier than Rabbet.