Most waveforms deal very badly with from black transitions (see: nightmode being a ghosty mess), so I've never been a huge fan of the white -> black -> image approach.
Black -> white -> image *might* help in some very specific circumstances, though?
But in most cases, on current devices, flash white, flash image works out just fine.
EDIT: I spout way less nonsense after a good night's sleep
. That's obviously why I insist on the "flash" part of the equation: that's precisely the mechanism providing a short switch to full black.