In my opinion, you don't really need a deep black in a pt/pd prints. If you look at the print I sent you, the borders are deep black, but the image itself doesn't contain any black areas. What's great about pt/pd is the long scale, i.e. the fact that there are so many shades of gray that can be represented. I agree that for silver prints, a deep black is something very desirable (although personally I love high-key images with no black as well) but it's not something you must have for a pt/pd print to be successful.