The phrasing of the questions at the start of the paper determine the answer they
get. They
have no idea what multiproxy averaging does. By their logic, I could argue 1998 wasn't
the
warmest year globally, because it wasn't the warmest everywhere. With their LIA being
1300-
1900 and their MWP 800-1300, there appears (at my quick first reading) no discussion of
synchroneity of the cool/warm periods. Even with the instrumental record, the early and
late
20th century warming periods are only significant locally at between 10-20% of grid
boxes.
Writing this I am becoming more convinced we should do something - even if this is
just
to state once and for all what we mean by the LIA and MWP. I think the skeptics will
use
this paper to their own ends and it will set paleo back a number of years if it goes
unchallenged.