You're not wrong BUT.
Aren't many of the scenarios we come up with here on this board based on assumptions? maybe the odds are low, but not astronomically, people who fit Hernandez's profile take one-year deals all the time. Even if it's more likely than not he does not, it's not a terribly unlikely scenario either.
And while I agree with your plate discipline, I try to look at that as the totality of the team. If Verdugo could bring in a guy who makes your pitching staff better, and Hernandez/Rafeala push Yoshida to DH I think the team is overall better.