Q: The Book of Blessings 1635 implies that the blessing comes at the end of the universal prayer, just as it would if given individually. Correct?
A: You’re right. I see it now. Yes, the priest concludes the universal prayer offering the prayer for health through the intercession of St. Blase without holding candles. He extends his arms over the assembly.
Q: What are you recommending for blessing of throats and ashes this year of the pandemic?
A: I’m recommending that the priest recite the prayer seeking the intercession of St. Blase as part of the final blessing of the Mass, just once, over the entire congregation.
I’m recommending ashes dropped on top of each person’s head instead of smudged on the forehead.
Both of those methods are permitted by the liturgical books.