Much of wardrobe my winter wardrobe is navy, grey and teal so a chocolate brown would work with those shades......I think.
I have tried to work in a few berry tones for this winter to brighten things up (I start out loving my greys at the beginning of autumn and then pining for colour by December!) so am thinking choc brown would work with those too??
I have a dark grey pair from Topshop, find it a really flattering but versatile colour with my summer/autumn (!) wardrobe. As you say, not as harsh as black. (My wardrobe is full of colour so a dash of grey won't kill it dead )