Interesting; I think the dates I came up with when I researched it put black coming in a good 10-20 years earlier than what you cite [with a lot of, but nowhere near exclusively, black in the 1820s-to-early-1830s which is, IIRC, our dance Regency]. I was led to believe Byron was primarily responsible for the fashionability of black, as he preferred it. I've also seen plenty of color in dated plates showing men dancing at balls smack in the middle of our period, and am likely to accordingly go with color [and carry a source] whenever I get around to making my own coat.