Leadsled:
"We have on the books some very serious/fatal accidents during training at night, that probably would have been less serious/wouldn't have happened at all, in daylight --- think Metro at Tamworth, light twin at Camden, just for two."
I call BS on your statement.
We also have an Embraer at Darwin Airport, 2010, and a Conquest at Renmark 12 months ago - both in broad daylight.
The aircraft doesn't know if it is day or night. You may describe this as a "glib statement" but it is a fact.