I am pleased to see on Fr Finegan's and Fr Blake's respective Blogs, posts about the Offertory antiphon. In the Mass there are three Antiphons, not two - Entrance, Offertory and Communion. The Offertory Antiphon is at the moment 'hidden', as it does not appear in the Ordinary of the Mass in the Altar Missal. However, its place and nature are described in the GIRM (paras. 37b and 48), and it is included in the Revised Roman Gradual. Without wanting to talk about the importance of this Antiphon, other than to say that it proclaims the beginning of the Liturgy of the Eucharist and expresses Christ's intentions as the Offertory of the Mass begins, we should be looking to build the reform of the reform by including the Offertory Antiphon in the Mass. The above mentioned Blog authors are right in calling upon those who are appropriately involved in the Liturgy to produce and insert these antiphon texts and accompanying chant tones.
I understand that the Revised Roman Gradual includes Offertory Antiphons taken from the Tridentine Missal but reorganised for the Novus Ordo. Whereas the new Altar Missal contains Entrance and Communion Antiphons which were newly written for the Missal. Also, I understand that there is an Anglican Gradual book, in Englsih, which also contains the three Antiphons organised for the Novus Ordo.
So, I add my voice those already calling for the Offertory Antiphons to be prepared and made available to be said or sung at the Mass - something which, clearly, we should already be doing.