Certainly such care and reverence is not a departure from the theology and practice of the Reformer himself, as has been amply shown here and elsewhere. But is it even the case that it arises only out of late medieval theology and rubricism? We might not be so quick to entertain such ideas if we go back a millenium earlier, and give a fair hearing to the early church.
And so, for example, from the third century, let us consider these words of Origen, who gives witness to the prevailing practice of his day.
You who are accustomed to attending the divine mysteries know how, when you receive the body of the Lord, you guard it with all care and reverence lest any small part should fall from it, lest any piece of the consecrated gift be lost.
As further food for thought, I suggest that this witness, in itself, implies the likelihood that this type of practice and level of care for the Sacrament predates the third century, and goes back into the silent age of the first few centuries, the age when the Sacrament was considered such an awesome mystery that it was considered best for the most part not to even speak or write about it publically, and comports with the care intimated in the New Testament itself, where, eg., our Lord instructs after the miraculous feeding in John 6, "Gather up the fragments that remain, that nothing be lost."