URL VS DOMAIN TRUST FLOW

If I can get a backlink from a url which has 0/0 tf/cf or low tf/cf such as 2/3, does it still worth to get a link from that considering that the root has a pretty high number? e.g tf/cf = 30/35.

Another question: my competitor has a link from a website with tf/cf 45/50, however the outbound links are over 2000. Is the link juice way too diluted to bother getting one, or it's still worth giving it a shot?

First question: the majestic crawler probably missed that internal URL. It still passes TF, IF it's not blocked by robots.txt or a cloaked page from google.

Second question: forget about any link in a page with more than 100 links in it.