Chantry Foundations in late Medieval England (2)

Among the impressive relics of the Percy family, who dominated the North of England until the jealous Welsh eyes of the Tudors fell upon them, is Warkworth Castle. It keeps watch, its (intact) Great Tower for all the world like a skyscraper keeping a lordly eye over all Manhatten, over the eiderducks and curlews and waders and oyster catchers of the meres surrounding the estuary of the River Coquet. And, just up the river, is "The Hermitage".

I'm confident that it wasn't a hermitage; the first documentary evidence (1487) describes it as a chantry. It is carved out of the living rock, which has limited the degree of decay into which it has been able to fall. It is a chapel with what is identified as a side-chapel to the North of it; attached is a dwelling just like a substantial house in miniature: kitchen, screens passage, hall on the ground floor; above, solar adjoining the chapel. From the solar there are four slits through the West wall of the chapel enabling worshippers there to partake in Holy Mass.

Imagine that you are standing at the Altar offering the Holy Sacrifice. Immediately to your left (North) is a wall opening with expensive tracery (and ferramenta suggesting that it was glazed) offering a view of the action of the Mass to somebody kneeling and facing South in the possible side-chapel. Immediately to your right (South), occupying the sill of a window which looks onto the outside, is an almost life-sized piece of sculpture which has, I think plausibly, been discerned as a Nativity scene: our Lady in child-bed with S Joseph at the foot (West) of her bed, and (much eroded) manger animals behind her (i.e. to her South).

Somebody kneeling in the 'side-chapel' would look out through the ornate tracery directly onto the Altar and the celebrant, and beyond the priest would see the almost life-sized (and certainly richly painted) Nativity scene. If there was no priest saying Mass, the viewer would look directly onto the Nativity scene ... rather like kneeling at the Crib.

This set up a lot of queries in my mind. Do learned readers know of parallels to a set-up in which a privileged worshipper looking out onto an altar from its left would be provided with a sumptuous devotional object of devotion the other side of the altar? Do you know of other chantry chapels a few hundred yards along a river from a noble family residence? At Alnwick, there was Alnwick Abbey a stone's throw from the enormous Percy Castle there: might the chantry at Warkworth serve a purpose there which would be served at Alnwick by the nearby Abbey? The Percys were not buried in Northumberland: does a sumptuous chantry provide a substitute (a sort of cenotaph) for the opportunity to pray at the burial place of ones forebears? Might the Earl have gone to Chapel to make his confession?

What I am particularly after is evidence and parallels.