How to tie up to a mooring
Now I think I understand the question. Well, I''m not sure how much chain should be on the mooring. I''m sure someone on here knows better than me. The pull being straight down isn''t a problem, it just means your boat isn''t putting any strain on the mooring system. The mooring mushroom or whatever depends on its weight and being buried in the mud for its holding power. It is not like a typical anchor, such as a Danforth, where you need a shallow angle pull to keep it dug in. Even if it were an anchor, the fact that the chain is dropping straight down means there is no strain on the system so there would be no danger of breaking out. I don''t know if I''ve even come close to addressing your questions!
I''ll let someone else jump in here with opinions on how much chain there should be.