Assuming we have two objects (a peg and a fixed hole) the xml descriptions seem to allow defining some of geom parameters such as friction, solimp, condim, solref independent for each. Is there an intuition or difference for choosing these parameters for the peg and the hole differently? and in addition does switching them between the two objects make a difference? Would someone normally change the default value of these contact parameters or is it also common to change them only for a task related objects?