How many instances were the Tau'ri at least partly responsible for at least the partial destruction of a solar system? How many were deliberate? How many were accidental? What were the specific instances? The examples that come to mind first are when Carter causes a star to go nova (deliberate), when McKay tried to finish Project Arcturus (in SGA: "Trinity", accidental), and when the McKay caused the destruction of most of the Asurans (deliberate, but scale of destruction was unintended). There are a few other instances where SG1 or the Atlantis team had a hand in the destruction or partial destruction of a solar system, and some instances where it was implied as well (tricking the Aschen into dialing a black hole for instance). The destruction of Icarus base might also qualify. On a side note, is dialing a black hole and failing to cut the connection the equivalent of a new black hole being created where the stargate is, or would you consider it as just the effects of a blackhole lightyears away being transferred through the stargate?