Hey it's not voodoo, all they do is to damp the cheap thin glass of todays new tubes from ringing, nothing else. Nothing inside of the metal tube structure itself anodes, cathodes, grids, getters, heaters ect, as that stuff is all bonded to the base material. If you want dead thick glass you have to look at NOS tubes.
And no, any type of tube damper will not stop a tube from being microphonic.
Cheers George