Here's an article I've just finished that tracks Anthony Johnson's weight cutting issues for his fight with Yoshida.
It includes a number of video interviews, articles, etc that he did in the lead up to the fight where he talks about his weight. I think it's clear it's been a major concern for a good while despite his attempts to downplay it.
Check it out at the link below:
In future if we wants to stay at 170lb he's really going to have to keep at a sensible weight at all times whether he's injured on not.