The arrival of various hand-outs, bespoke orders of service and other small pieces of printed liturgical ephemera brings good and bad things to liturgical practice. Percy is not sure why, in an otherwise environmentally-sensitive context, there is so little thought given to the paper being consumed, for one thing. Yet there is no doubt that having all the elements needed by the congregation for full participation in one single printed form makes for ease of use and engagement.
Many will also point out that the full provision of the lections - assigned readings from the Bible - in such forms assists their reading and understanding by the people. It is also probably a reasonable hedge against the temptation to leave something out, which I have commented on elsewhere!
Yet some readers might well raise the objection that these photocopied excerpts are a poor substitute for the use of a Bible.
I tend to agree, if perhaps not for the same reasons as some of my more protestant readers. I do not, for instance, think it is particularly necessary or even helpful to bury one's head in either a Bible or a pewsheet when Scripture is read at the Eucharist. The Bible is designed to be heard as well as read, and the liturgy assumes a community willing to open ears, as well as eyes, to what the Word might reveal to us.
In fact for most of the history of Christianity, most Christians have not been literate, let alone owned Bibles; and hence, while we may be glad this is not the case for the average follower of Percy's thoughts today, it suggests that any view of liturgy or of Christianity that makes "Bible reading" an essential discipline is questionable, historically and theologically as well. Christians have heard the Word first and foremost, and the liturgy reflects this.
Yet the Book itself has a liturgical place which should not be lost. In classical protestant worship as well as in liturgy of self-consciously catholic traditions, the Bible has been not merely a source of the day's readings but a visual symbol, a key object in the work Christians do when coming together to remember, listen, pray and praise the God of the Bible. That Book ('B' for emphasis) is not the various books (i.e, Bibles) individuals might bring to Church, even if their contents are the same; for the Christian does not - should not - engage with the Bible as a personal tool of revelation via private judgement, but as the corporate gift of challenge, encouragement and more.
For this reason the actual use of literal physical books in liturgy is significant. The Book or Books from which Scripture is read liturgically should reflect that corporate and public function - meaning that above all, such Books should actually be used, and visibly.
How exactly the Book is used depends a great deal on the space and the specifics of the liturgy. A large Bible visible on an ambo or lectern makes a clear statement (and shouldn't be visibly pushed aside for a preacher's folder, pewsheet, or iPad). Visibly reading from photocopied sheets leaning against that Bible is also not a good look. Pewsheets are not intended as a hedge against biblical illiteracy, and if necessary readers should expect to be trained not only in how to read aloud, but in where in the Book to find what they are supposed to read.
In some contexts different Books are used, most obviously when a Gospel book or Lectionary is carried in procession. This makes a point about the (generally overlooked) centrality of the Gospels in the Christian canon for interpreting Scripture as a whole, and the proclamation of the Gospel to the world. There are quite a few places where the idea of this procession appeals just because it involves some pomp and circumstance, but where the point gets lost. Such a failure is ritualized, for example, where a plastic binder or the mere pewsheet gets hoisted by a deacon or other offender, to general bemusement. The liturgical proclamation "This is the Gospel of the Lord" is not meant to be so implausible.
Of course there are times when a set of readings has to be prepared for a set of readers, in ways that make the idea of endless bookmarks or post-it notes in one Book on the lectern impractical. In that case, there are various possibilities. The assembly of set readings in Lectionaries - not originally lists of readings only, but the actual texts - has a venerable history. Yet these books have traditionally been treated with the same respect and prominence as Bibles and Gospel Books, and there is no reason they can't be made or decorated to make their dignity match their amenity.
The basic principles about using books are thus those of the liturgy as a whole. The Gospel itself, Christ himself, are the centre. Our actions should make this as clear as possible, and we should minimize or avoid things which distract from what is important. The Bible is important. Words can make this clear, or undermine it; so too can objects and actions.