A very powerful piece of writing. Without in any way wanting to take away from your argument in relation to the Spanish Civil War, which is compelling, I would argue that sometimes the ‘blandness’ of archaeological documentation is just as inappropriate to events that occured in the much more distant past.
Taking an example from my own experience, I was recently involved in excavations of the castle near the centre of my home town of Bedford, UK. When the castle was captured and destroyed in the early 13th century, a total of 80 men from the defending garrison were executed by hanging in a single day. Although not on the scale of some of the massacres and war crimes you mention, as a local event it must have severely traumatized the community of the town at the time. Its just so easy, in writing today about a past event like this, to glamourize it while at the same time glossing over the sheer horror of it. I’ve done it myself in my own writing. Yet the sanitizing effect of ‘blandness’ – embodied in standard archaeological styles of reporting of violence long ago – must influence and be connected to our perceptions of violence in the present and more recent past.
Because of its ability to uncover and make directly accessible the material traces of violent acts, archaeology really does have the power to materialize or ‘bring to light’ the dark pasts that you speak of – but only if blandness is not deployed. This surely applies as much to distant events like the hangings at Bedford Castle as it does to more recent conflicts and atrocities.
Could it simply be that blandness does an injustice to the human past, no matter how recent or distant?