Good article, I do wish it would talked about big-O and arbitrary sort orders.

Let's say there's lots of columns/fields to sort by. Not quite an arbitrary sort (e.g. can't sort by area when given a width and height column) but its still pretty flexible. Is is possible to get a O(1) pagination while avoiding the rolling-shutter problem and deleted-anchor problem?

Getting around the deleted-anchor problem with ordered-ID's seems like just using ID's as a index. Not a bad trick, but seems like it isn't generalizable for all different kinds of sorts.