I haven’t taken the course but I read the manual on valsalva technique a few years ago. I think one of the useful things I took from it was to become more aware of laryngeal tension. It’s an area where many people carry excess tension (whether they stutter or not) and it is really helpful to be able to feel when your larynx is tight and when it is relaxed. Before challenging situations I will now repeat to myself “slow and open” to remind myself to modify my speech - the open part refers to a relaxed, open vocal tract. There is an exercise that is used in voice therapy (so not designed to be used in stuttering therapy - but I find it helpful) called the yawn sigh. https://youtu.be/A4_L6tfKnY0 . This can be a useful way of putting your vocal tract into an open position. I find I block much less when I have prepared myself in this way.