Well, seeing as it's Hogmanay…
I've SS-ed for many (many) years, both commuting 700c and offroad 26". As others have said, 32/16 (or any other 2.0 ratio) is perfect. I did TransScotland over 7 days on 32:16 and all was well. On 700c (Pompino, drop bars, CX tyres), I'm currently on 2.5 (40/16) which is great.
However, here comes Strathpuffer. I rode 32:16 last year & the year before and it was far too blimmin hard. Also I fell off and broke my knee when I was dead tired in the snow at 2AM, and I couldn't get traction. So, I have an 18 and a 20 in the shed. Depending on conditions I'll start high and get lower.
All that matters is the ratio, so for 32 up front and assuming a 2000mm tyre outer diameter (on the low side of correct) it's as follows per pedal revolution. Multiply this over just 10 revs and you can see why the difference is so noticable in practice:
32:16 = 2.0 = 4m
32:17 = 1.9 = 3.8m
32:18 = 1.8 = 3.6m
32:19 = 1.7 = 3.4m
32:20 = 1.6 = 3.2m
Cheers, al.