I've concluded that for Seattle conditions (low 40s and steady rain) the magic setting is: full recirc., face and feet vents, heat and AC lights on, temp at mid-60s. Fogging was driving me crazy over the last rainy week using various combinations of fresh air and windshield, heat only (AC light off) or feet/windshield vents, or the mystery mode and feet only. Finally tried full recirc. with AC on yesterday and cleared the windows well without too much power consumption shown on the displays.
2013 SV no QC, manufactured July 2013
car grew up in San Jose CA, purchased 5/31/17 in Seattle
on 6/16/17: AHr = 56.4; SOH = 86%; Hx = 84.3; ODO = 39,250
on 9/29/17: AHr = 55.3; SOH = 84%; Hx = 81.6; ODO = 41,492
bar 12 lost 8/21/17