I think that means that i do bother with the most obvious spots, mostly because it freaks my husband out a little, but i don't get obsessive about it. It appears to me to be very fatty, and you can't see it after you cook it. I don't think i've paid attention specifically to whether it cooks...
Are you talking about the black stuff that's kind of underneath the skin?
I get that most often when we butcher dark birds like BSLs. I've found that i can use my finger nail to kind of press and push it out of the pores. I don't worry too much about it though.