I've used Blood and Bone (very old bag, I was given a 50# bag) on and off for a number of years in a mixed collection. For me, it works best in a relatively dense media. I often use a modified Off mix with about 12% peat and this seems to work well with this fertilizer. This would mainlyl be Phals, Catts and Dens. I've had just about the same results with NZ sphag, maybe better growth. Paphs do okay as well in this kind of medias. I now use a more open mix w/o peat and the Blood and Bone doesn't seem to have any effect (for Paphs).
I think the media seems to break down faster using this fertilizer.
It needs to be applied relatively often. I think it lasts about 3-4 months in Hawaii. Very warm, humid and bright conditions.
I haven't tried the tea bag, but I did try tying some in fabric assuming some will drip into the plant with no results. A tea bag would probably do better.
Years ago, I met Miya (Masatoshi Miyamoto.) He was broadcasting this over his compots that were planted in peat/perlite mix in clay pots. Catts and Dens. Literally hundreds of compots. So I guess it works, very old school, but it works.
I think there are better ways to fertilize unless you had a specific reason to use this, like going green or you got a 50# bag for free.