Dyn-cloth engines may get better results with a triangulated mesh. May. A big piece of fabric felt down to ground for example. But tri-mesh != tri-mesh. One has to find out which routine gives the best result in a certain case.

That does not mean that you need to construct your model as a tri-mesh from the start. You may make a tri-meshed copy from your quad-mesh just before going to the dyn-engine (I think that's what Earl meant).

---