Let me suggest something: let’s throw some chicken bones in the air and see what pattern they make when landing. Or lets read the scratch patterns of the common street pigeon. Because we have much better than those proxies and we are still going for them. Look at the crops and where grew what. There are records – especially for the Roman warm period. The Romans were keen accountants. If crops grew in regions that are too cold today for them, it must have been warmer than today. If there were lush forests in Greenland where are none today it must have been warmer. If mountain passes that open up just now were open in those times it must have been warmer. But we go for tree rings. Fine, but if I have a choice between direct evidence and another proxy I am a madman if I use the proxy.
If the persistence tendency is correctly taken into account, the current warming of Europe appears even more exceptional than previously assumed.”