The act of placing toilet paper in the bowl before taking a potentially large and therefore loud dump. Not to be confused with a "poo lasagne" which has a similar process but is purely for comedic effect.
The crashmat has several beneficial properties. It is incredibly useful for:
1. Muffling the splashing sound of poop hitting the toilet water
2. Preventing skid marks in the bowl
3. Ensuring there was paper in the bathroom beforehand
4. Aiding the poo on its journey through the u-bend
"I had to lay down a ferocious dump at my in-laws house last night while they were asleep. Fortunately I laid down a crashmat so no one heard that bomb when it landed."