A lot of PWS may start scratching their heads that why do we need to stammer with audible blocks when going through with silent blocks can make it less embarrassing for us.There are some genuine logical answers for your query :
1. Audible open speech blocks do promote ACCEPTANCE and hence lessens the struggle and pain.
2. Audible speech blocks are smaller than silent ones.Hence, will be less bothering the listener as well as us, the stammerers.
3. Making speech blocks audible helps us having better control on our speech. Making the speech blocks noiseless will take away the control from the speaker and next 3-4 words after that block will come out of your mouth just like retained water freed from the dam i.e. very very fast and very difficult to understand.
4. Silent blocks makes us short of breath and hence very difficult to continue rest of the talk.
These above points have been drawn by a lot of PWS by their own experiences and I do experience every bit of these lines.