I was wearing tights and shorts under. Did not matter, still got a large and deep road rash. Crazy thing is the elbow rash, about 4 inches diameter, occurred with a Navara wind/rain jacket, a long sleeved wool Ibex jersey, and a long sleeve mid weight merino base layer. None of the layers were torn or damaged yet the rash was deep and bloody and extended into the bursa of the elbow.
Gauze by the way is not a good dressing choice. I have been using a bordered polyurethane foam over silver alginate. With this dressing one can keep it on without removing it for up to seven days. The less you remove the dressing the better and faster it heals.