Honestly, if you are not looking for it......you probably won't notice it. Maybe it has been done to you and you didn't see it. When we did it,(40-50 times) neither the umpire or the other team ever noticed.
This move was taught to me by a college pitcher......I asked him if it was a balk...he said he didn't know if it was a balk or not.......but he did tell me that his team would do it frequently and his coach didn't think it was a balk....and....no umpire had ever called it.
Like I said, until I started to study for my IHSA test......I never knew it was a balk.
I monitor this site and other umpires sites so I can be knowledgeable of the rules. Unlike you folks......most umpires I have encountered (rec, travel, & high school) are limited in their umpiring knowledge. It is very frustrating sometimes....many of these guys are out there just for the pay. Recently I had an umpire tell me that "the hands are part of the bat"!! I didn't argue with the idiot, but I did quietly tell him that was a myth and he could check it out on the internet.
I'm a coach, and you don't know what I have to put up with.......I don't argue much.....I carry rule books with me......and I have filed a protest (I won the protest) when an improper "fielders balk" was called in a Bronco game against my team.
I always enjoy having knowledgeable umpires at my games......however it is not as frequent as I would like.