I think that the complexity that this proposal is proof of its failure.
If you look at a Feed document as simply a sliding window view into the historical state of entries instead a sliding window view into the current state of entries (though as I have shown these can overlap),` then you have your archive document already.
HELLO GUYS/GALS YOU ARE THERE AT THE FINISH LINE. IT ALL WORKS!
One of the arguments against the sliding window view in the historical state of entries is that it was too complicated. But clearly not going that way is making things WAY MORE COMPLICATED.
So before proceeding any further it may be worth now comparing the
complexity of both proposals in detail. My guess is that the historical one is just a little surprising, but that is all.
Henry Story