My short term solution: I start the sentence over and see if it flows better. My long-term solution: learning to relax the face, neck, mouth and tongue during blocks. Pretty much, if I know I have to talk, I take a moment and breathe. I consciously focus on relaxing my face (thanks, yoga). Does it always work? No, but I've been doing it for years and it does help. Phones are still hard for me though. I'm terrible on the phone because I don't often get that moment to prep. The phone rings and I have to answer. To answer your question: I try not to force. Forcing leads to the stutter part. Sometimes, there's just no getting around it though!