Lay persons may perform this task, but the Church insists that such service be limited to truly extraordinary and compelling cases. Simply the need to shave five or ten minutes from Mass time is not an acceptable excuse. Any parish that uses such assistance on a routine basis is breaking the law. I have already explained why it’s a particularly bad idea for women to perform this service.
It ain't insistin' very loud -- especially as heard through the filter of the USCCB! Of course, then too, I'm in Boston -- if I were a true gambler, I'd be making book on whether Boston will go into open schism when the clarification of the MP comes out! ;-) (Smilin' on the outside, . . . )