I agree with rumr.. I climb with people who are bigger than me and I never clip to the floor inside. outdoors when some one is on lead is a diffrent story and I look for a good anchor for myself... but if there isn't one I know I will be okay because I have practice securing a fall and throwing my own weight arround. with out a bottom anchor it gives a nice dynamic belay.
it doesn't make any sense to me to use a static rope for top roping...the fall would be painful. what a way to turn people off of climbing.