to Paul Barford

Paul,
Look at:
http://www.bbk.ac.uk/hosted/leonardo/#HH
You could have asked. I have a website and available email.
Have you read the original book?
Have you seen the drawing, at least in high res?
Do you know about vellum? Have your tried cutting it?
Do you know about the production of specially printed books on vellum?
Do you know about the other versions in London and Paris and their foliation?
Etc etc.
One placement in the book is, as is clear in the narrative, to match where the stitching is most visible; the other is the actual placement.
A small sample was used for the carbon dating, obviously. The thickness was measured thus.
Poland has not been "dragged in".
We have a responsibility  as historians to use language properly and not to post such assertively categorical comments without checking adequately.  Amateur, irresponsible and damaging.
Pascal Cotte has prepared a point-by-point rebuttal.