My pastor never uses the third form penitental rite, as such I never get a chance to lead the innvocations. I mentioned this to him once and he said that third form is not permitted for Sunday. I think it was a little bit of a knee jerk response since at the seminary the third form was always used and the deacon would lead the innvocation.
This scenario strikes me like the time we were discussing how we should process in. He wanted me to walk infront of him, and concelebrants if any. I told him my place is at his side and concelebrants are infront of both of us if any. The only time I would not walk by his side is when the Book of The Gospels are used. Just in time for the first mass where I would assist he found a copy of the Book of the Gospels
Does anyone have a definite answer to this liturgical question?