In the OPA454 datasheet I found an interesting circuit idea that I'm not sure what is it usually called (if there is a common name for it).
It involves using two opamps to shift the rails of a 3rd one. Note that unlike a bridged [tied load] configuration this circuit requires a doubling of the voltage supply rails. On the other hand, the load is not floating in this circuit, so you can combine ts idea with the bridge to get 4X the output voltage swing (relative to using a single opamp). I'm omitting the 6-opamp bridged picture here as rather obvious; you can find one in the aforementioned datasheet.
My question is just what's a/the common name (if any) for this circuit idea. If I were to coin a name, "dynamic rails", "dynamic operating point" or something like that seems reasonable to me. (But these names don't get any sensible results back via google search.)
EDIT: I also saw something similar, but cheaper, with two BJTs instead of opamps for the "rail shifters" (A1 and A2) in a 1999 EDN article titled
"Bootstrapping your op amp yields wide voltage swings" written by [then] AD employees Grayson King and Tim Watkins. Using BJTs would introduce some more non-linearities, no doubt. So maybe "bootsrapping" might be the name for this technique...
although Rod Eliott's page discussing the issues with this approach never calls it that, so I'm not convinced "bootstrapping" is the name for it... (EDIT3: Well, this was an incorrect reading of the purpose of that circuit; see comment below the question.)
EDIT2: In another article and in AD app note AN-232 (cited in that article), "supply bootstrapping" or "substrate bootstrapping" refers to something similar (altering the rail voltage via "feedback"), but in these articles it is done for a different purpose: a reduction of the input capacitance non-linearity for opamps with FET input stage... So, I'm guessing "bootstrapping" encompasses the idea I've asked about, but can generally mean the use of this supply-voltage-shifting technique for other purposes.