I have situational stutter and blocks as well, it’s very frustrating. I was once really scared that it would hinder my career, but the truth is that my career is unaffected. Not every employer expects you to speak perfectly and if they do, that IS wrong on their part. It does depend on the job somewhat, but it sounds like you know you’re capable. I say that you’ll eventually find an employer that doesn’t care about the stutter, sees the potential in you, and that you’ve probably been unlucky so far. Do you address the stutter in the interview? Meaning, do you say something to the effect of, “sometimes I stutter, but in no way will this impact my job performance”? You may already be doing this, but that’s probably the one thing I would implement.