This is merely a new way to implement a ubiquitous and venerable concept: price discrimination. There is hardly a thing in the world that some man can not make a little worse and sell a little cheaper.

gawker: The ever skeptical [Norman] Mailer knew more about what was going on than he let on, saying in 1964's The Presidential Papers that: "At bottom, I mean profoundly at bottom, the FBI has nothing to do with Communism, it has nothing to do with catching criminals, it has nothing to do with the Mafia, the syndicate, it has nothing to do with trust-busting, it has nothing to do with interstate commerce, it has nothing to do with anything but serving as a church for the mediocre. A high church for the true mediocre."

Griftopia (2011) by Matt Taibbi.

Remember that famous Alan Holub piece from 2003? Why extends is evil
Improve your code by replacing concrete base classes with interfaces
By Allen Holub, JavaWorld.com, 08/01/03

There's a name for the pitfall risked by this strategy: overjustification effect.

The technology in question reminds me of VTD-XML (Virtual Token Descriptor). Make an index that points into the document, "starting offset and length" as described here: VTD in 30 seconds. i4i's "map" is VTD's "index" + "location cache". But no one's talking about it.