The scola does it at the seminary. A good question would be to ask anyone who has spent much time at the Winona seminary if the scope ever did this. I assumed it is something only done by clergy, if present, but considering the Virginia seminary chapel layout, there isn't room for a scola, so they form a circle in the middle, which allows the rest of the clergy to see the scola director.
I assume others have observed this, and that there is a wide spread assumption that if the seminary does something, every church should. Similarly I have seen and heard of traditions of serving mass coming to other chapels from the seminary.
Not everything is some secret modernization; often there are reasonable explanations. With the new live stream available from the seminary, it is likely many churches will adopt new traditions observed there.
I agree with this response, and I know it was done at the Seminary when it was in Winona too. I don't know if it was
always done there, but there was a 2010 docuмentary on the Seminary where it shows the schola in that formation.
Matthew might be able to tell us if that's what the schola did when he was there.
Given that this is what the Seminary does, it wouldn't be surprising if that's why these chapels do it too. Why they would
switch to doing it that way all-of-a-sudden when they didn't do it before might be a different story, but the Seminary doing it likely might be a reason nonetheless.