Are blackface morris dancers rabid racist bigots?

It has been many years since I have seen English morris dancers perform, but my memory is of a bunch of quirky but harmless white dudes with bells on their ankles skipping around to folk music. I never saw any, but apparently there is also a long tradition of morris dancers painting themselves black for their perfomances (note that I deliberately avoided saying "performing in blackface", because that automatically confers a pejorative connotation, as though it is deliberately done with racist intentions aforethought).
Now, I have no reason to suspect that morris dancers are a thoughtless, racist bunch. They just have a much more developed respect for old English folk traditions than I do. But, of course, anything involving "blackface" automatically becomes a political hot potato. There have been heated academic debates over whether the tradition in question (a very minor and rare variant of what is anyway an obscure and uncommon pastime, let it be said) originally developed long before black people - and therefore racism - were even known in Britain, or whether this particular variant of an ancient artform was actually influenced by American minstrel shows, and even if it was does this then make it racist in intent or in effect.
Some researchers argue that the tradition arose from performers dressed as chimney sweeps or miners, or that they were agricultural workers disguising themselves to avoid recognition by their bosses. And then, of course, there is the argument, put forward in this article, that the historical of the tradition is entirely irrelevant, and that the practice should be banned anyway, just in case it causes offence. But do we know whether black people even find it offensive in the first place?
I am in no way advocating deliberate racist offensiveness, which I have lambasted many times in this very blog. But this seems to me to be just another example of bleeding heart liberals - and I count myself among them, for the most part - twisting themselves in knots over an issue that may not be that important in the scheme of things, and that may even be misplaced entirely.