using black

for many years I have used black in my watercolours .and I cant understand the taboo,asociated with it .most well known artists used black may i indulge a little of your time with a few swatches that prove to me they used black and I admit to keeping secret myself , 1 here we have a mix of cobalt and black to give the beautiful Ted Wesson royal airforce blue (you show me how to get it any other way 2 here is a mix of cerulean blue and black (beautifull ted wesson blue in skys 3 mutted green made with black and cad yellow 4.and finaly a colour ted used often check out his Loch Maire scene )what a lovely striking blue colour black and cobalt