Bonnie, if I am not badly mistaken, DJ1 started its life to tap the shallow strata of the old oil producing areas. It was deepened to test a theory that there was indeed pay strata in the ultra deep close to shore. DJ2 was intended to go to the ultra deep from the beginning.
Information gathered about the various strata along the way has caused a radical change in some of the old thinking about what is really down there. Depending on the results of the much anticipated flow test, we may see a whole new world of oil and gas operation in the shallow water fields.