Let me premise these comments by apologising in advance for what is really a bit of a rant. I love the sung mass.
I go to a low mass in the absence of one - and in strong preference to a novus ordo, all things being equal. But I still regard the low mass as a very distant second best. I don't mind the silence at the Offertory and the Canon of the Mass (quite the contrary- I think it works at that point).
But although I'm doing my best to learn to love it, I have to say, the silent version of the prayers at the foot of the altar bothers me. And Mass with the priest saying all the responses, something I experience often enough to be an issue, bothers me even more. In fact I wonder if both these practices are not abuses (ok, the former one maybe not strictly speaking an abuse but still...).
Why every Mass should be a sung mass!
I guess my view is that a low Mass works well at a (beautiful) side altar with a very small congregation. Even more so when several Masses are happening simultaneously. But in a larger (and often uglier) Church, it is hard for its intrinsic merits to be as readily appreciated.
One of the peculiarities of the Low (traditional) Mass in my view, is the wide range of different approaches to saying it. Take volume. Some priests say it virtually all sotto voce. Some say everything except the silent bits quite loudly. Some servers follow the priest in the volume they use - others murmur their responses inaudibly even when the priest speaks quite loudly.
Personally, I want to hear these prayers (and the other things the rubrics indicate should be spoken in an audible voice such as the readings) - not least because it is hard to assist at something if you can't even tell whether or not it has actually started!
A traddie touchstone?
The prayers at the foot of the altar seem to be one of those touchstone issues for liturgical purists - the french Benedictines for example, regularly seem to get blasted in various forums for dropping them in the conventual mass when it is joined to one of the hours of the Office (presumably the theological rationale being that the priest was well and truly prepared to celebrate the sacred mysteries by the liturgy he had just sung).
I have to admit I find it hard to get worked up about whether or not they are dropped a la 1965 or not. True they are rather beautiful. But in the sung mass of course, they are completely inaudible to the congregation (not that that's necessarily important), and personally I tend to get distracted by the singing of the Introit. There are other ways for both priest and congregation to prepare adequately.
But if they are being said in the low Mass I do like to hear them - particularly the Confiteor (especially in the absence of it being said before communion - I want that Absolution to be clearly applied to me)!
But as I said above, some priests say them audibly, others don't. In fact Valle Adurni recently related the story of an Oratorian priest who felt so strongly over the issue that when a ruling came down that the mike had to be on for them, refused to say the TLM publicly at all.
The theology of the prayers
The rationale for the inaudible prayers, I gather, is that this section of the Mass really is between the server and the priest - they are, after all, the ones who are entering into the altar of the Lord.
The logical extension of this view is that if there is no server, then a person from the Congregation shouldn't step in and give the responses. And, as I've recently discovered, there are priests who take this view. Some won't allow a woman to say the responses. Others won't allow anyone.
I think there are two problems with this view, one theological, one rubrical.
First the theology of the prayers. While they certainly focus on 'going in to the altar of the Lord', a restrictive interpretation of this seems over-literal to me. After all, the priest has actually already gone up to the altar once.
The prayers are after all, meant as preparation for offering the Mass, and all of those present, as Mediator Dei points out, assist in the Mass, albeit not in the same way. While the psalm that forms the centrepiece of these prayers talks about going into the altar of the Lord, and can be taken as referring to the clear separation of priest and people in the Jewish Temple, unlike the Jewish approach (or the Orthodox), that level of rigid separation where the sacrifice is conducted behind closed doors, is not part of the Latin rite of the Mass as we know it today.
In fact, St Robert Bellarmine's commentary on the psalm puts the Introibo ad altare Dei verse in the context of Apocalypse 5 ('Though hast made us to our God a kingdom and priests'), pointing to the priesthood of all the baptised, rather than just referring to the Ministerial priesthood.
True, the priest acts for and on behalf of the people at the altar, standing as alter Christus - but, as Pius XII put it, he also acts 'in company with the people'.
The second issue (and closely related) is the idea of Mass without a server and without anyone making the responses. Saying a Mass without any ministers was repeatedly condemned as an abuse in years after Trent.
In fact Canon 813 of the 1917 Code of Canon Law (which surely applies to the 1962 Mass) specifically says: 'Sacerdos Missam ne celebret sine ministro qui eidem inserviat et respondeat.' Sub-section two of the same canon goes on to allow someone from the congregation, even a woman, to make the responses in the absence of a server if there is a good reason for the Mass to proceed (such as, presumably the presence of a congregation at a scheduled mass).
So I think the prayers at the foot of the altar should be audible, and if necessary, said by someone in the Congregation! But am I missing something?
Of course, the ideal solution is only have sung Masses...