I've stuttered all my life, but didn't develop speech blocking until I was almost 18 years old. It was really crushing because I thought the stuttering was bad enough. I don't know a lot about recovery per say, but if I am really stuck on a word, or know I am going to be stuck on a word, I find that either clearing my throat/pretending to cough, and picking a new word can really help move the conversation along. If I know I'm going to block on a certain word (can feeling it coming), I'll sometimes pretend to cough so I can buy a few seconds to find a new word to use. It's not technically helping the speech blocking, but it does help me move through it.