Bro where I'm at, stuttering or any disability that may hinder your work is extremely looked down upon. Especially when it is a calling process with sales(which is where i worked) I had to hide my disability from the get go, from interview to training and when the time came to take calls, it felt like I was living my worst nightmare. However I still kept it hidden and when my supervisor would tap my calls, he just thought i forgot words in between and I didn't mind correcting him haha. But yes, I still did stutter between calls, 1 or 2 blocks with some vowels but i managed alright. As for your second question, to be honest it has helped me a lot, it is absolutely anxiety inducing and it still does when I speak on calls but this habit of daring myself and challenging myself has helped me, found a lot of different ways to get around a sentences, speaking constantly helps too as opposed to keeping quiet in fear of that anticipation about "as soon as I speak I might stutter" I just say "fuck this" and do it anyways. I need to speak for a living. Hope that helps :)