Those can be great tools if you want to be fluent at a precise instant to me. I really like the simplest ones, which are just "speak in syllables" and "slow down your speech", if I want to talk without possible misunderstanding for like 30 seconds But I feel like either their effectiveness is limited, either I'm using them wrong. Like if my stutter is mid, I don't like using them on the long run, as it also requires a bit of concentration so tire me, so I just stutter as bit and speak after. And if my stutter too strong, even these techniques become ineffective (I still stutter and block), so then I often tend to go back to repetitions, forcing myself through a block, etc. (this happens especially when I get tired of talking).