Tony,
I’d be very interested to see what you consider as more accurate graphs of the MWP (called MCA by some) and the LIA than shown here:
http://www.sciencemag.org/content/326/5957/1256/F1.large.jpg
Sea surface changes in the AMO, ENSO, & PDO, are separately considered in creating these graphs. Note especially the interesting and obvious shift around 1300 in all three of these as we moved from the generally warmer period of the MWP (or MCA) the the generally cooler period of the LIA.
This graph was created by Michael Mann et. al. in 2009.
Anyway, I’d be very interesting to see your data for the same periods.