Things like test weapons in crucible, internet connection, needing to stand in a zone in control to capture it, bounties which change they way you otherwise play, playing alone or with very weak or strong teammates all come into play along with many other factors as well. private matches might be the best way to tell if they ever happen then you have gamebattles or mlg tournaments to better decide but Destiny wasn't ever really suppose to be about this side of gaming in the first place. that having been said I would welome private matches for clan battles.