Fread, I too saw Josh at the Albert Hall and agree that he was an excellent musician. The string breaking schtick was interesting to say the least and some of the material was a bit naff. BUT Josh was making his living by being an entertainer which means catering to the masses or a least a goodly number of them and by doing that material he was able to obtain a reasonable living. If he had catered only to blues aficiandos we probably would never have seen him in the UK.
Some people criticised Broonzy for leaning more on "Folk/country" style blues in his later years (and having a publicity photograph taken dressed in denims)rather than the up-town stuff which he had played in Chicago. Short answer; the guy was trying to make a decent living.So let's be thankful that at least we had a chance to SEE and hear just how good they were.

In the early sixties the blues audience was tiny in the UK. I was also at Muddy Waters and Otis Spann's first UK appearances and the mainly jazz audience were very scathing. Electric blues was not for them.