http://ntrs.nasa.gov/archive/nasa/ca...1979077159.pdf

Note the date...February 1964. This was very early in the development process. I found it interesting that the Mylar on the CM exterior was integrated into the design some time later, and was a main reason for the Launch Escape System being designed to completely cover the CM in the launch phase, to protect the CM surface thermal control covering.
Lots of interesting analysis of the problems here, problems that needed solutions.