Indeen! I've been taught that securing the trace eight could be dangerous when, in case of emergency, another rope is (supposedly) attached to the trace eight, but accidentally attached between the trace eight and the securing knot.
Same if you're lead climbing, there is a small chance (if you left a longish tail end) to clip the wrong part of the rope. If if it does not directly result in a dangerous fall you might trap yourself inside a quickdraw.
