Oh I know!
My first mule deer hunt, it was early-Nov and cold, well cold for NM anyway, still it was cold! so me being cold blooded I thought I would be smart and put on two per of thermals
Not such a good idea! See here in NM it gets cold at night, but will warm up by about 20* in the day, two thermals dum dum dum dum thing to do

Live and learn