Actually, now that I spent a little time thinking on it, this idea becomes even more interesting. Remember, one of the recurring themes that makes Harry so cool is that he has different conceptual limitations from the rest of the wizards. Now, as far as we know, dementors are controlled by people’s expectations. The reason that dementors haven’t exterminated all the life on Earth yet could be that while people are afraid of death, death always seems to wait another day and moves slowly and on its own pace. I mean, for a medieval person, the image of death might be connected to a tiger or a warrior on horseback killing you or disease or hunger doing you in over the course of several days or maybe weeks. Barring freak accidents, the fastest death-related image in a medieval person’s brain could be an arrow (or a fast-flying but perfectly dodgeable Avada Kedavra bolt for a wizard).
So, the Wizengamot people whom Harry considered unleashing a dementor upon, and the Death Eaters surrounding him now—they are all medievals. Voldemort, at least, has contemplated nuclear missiles, rockets and spaceships, so for him death could imaginably be something that can cover a good portion of Earth’s circumference in under half an hour, reenter the atmosphere at many times the speed of sound and blow a whole city to the oblivion. Voldemort, however, haven’t internalized as much physics as Harry did, so he is on the level of a mid-20th century science fiction writer—and he doesn’t have the power to control dementors.
Harry, however, is a totally different case. Harry can imagine (and, quite possible, given time and money, construct) a laser cannon that shoots a ray of death at the speed of light. Harry can think of supernova blasts covering interstellar distances. Harry can think of ultra-relativistic projectiles carrying enough kinetic energy to completely blow a planet apart. Harry can think in terms of homing missiles and AI-directed weapons that can track and destroy enemies without a need for human guidance. Hell, now that Harry knows that time-travel is possible in this universe, he should be able to realize that this could lead to FTL signaling (which could be used to kill people faster than light), so in his mind, death literally shouldn’t have a physically set speed-limit. And with his Partial Transfiguration, Harry already has demonstrated his capablility of using his knowledge to bypass the concepts that hold the rest of the wizards back. And Harry does have the power to control dementors.
So, to summarize the above—Harry is the only person who can truly control dementors, and in his mind, Death has no speed limit. If Harry can figure this out within the remaining 60 seconds—Voldie and Death Eaters simply don’t have any chance.
Actually, now that I spent a little time thinking on it, this idea becomes even more interesting. Remember, one of the recurring themes that makes Harry so cool is that he has different conceptual limitations from the rest of the wizards. Now, as far as we know, dementors are controlled by people’s expectations. The reason that dementors haven’t exterminated all the life on Earth yet could be that while people are afraid of death, death always seems to wait another day and moves slowly and on its own pace. I mean, for a medieval person, the image of death might be connected to a tiger or a warrior on horseback killing you or disease or hunger doing you in over the course of several days or maybe weeks. Barring freak accidents, the fastest death-related image in a medieval person’s brain could be an arrow (or a fast-flying but perfectly dodgeable Avada Kedavra bolt for a wizard).
So, the Wizengamot people whom Harry considered unleashing a dementor upon, and the Death Eaters surrounding him now—they are all medievals. Voldemort, at least, has contemplated nuclear missiles, rockets and spaceships, so for him death could imaginably be something that can cover a good portion of Earth’s circumference in under half an hour, reenter the atmosphere at many times the speed of sound and blow a whole city to the oblivion. Voldemort, however, haven’t internalized as much physics as Harry did, so he is on the level of a mid-20th century science fiction writer—and he doesn’t have the power to control dementors.
Harry, however, is a totally different case. Harry can imagine (and, quite possible, given time and money, construct) a laser cannon that shoots a ray of death at the speed of light. Harry can think of supernova blasts covering interstellar distances. Harry can think of ultra-relativistic projectiles carrying enough kinetic energy to completely blow a planet apart. Harry can think in terms of homing missiles and AI-directed weapons that can track and destroy enemies without a need for human guidance. Hell, now that Harry knows that time-travel is possible in this universe, he should be able to realize that this could lead to FTL signaling (which could be used to kill people faster than light), so in his mind, death literally shouldn’t have a physically set speed-limit. And with his Partial Transfiguration, Harry already has demonstrated his capablility of using his knowledge to bypass the concepts that hold the rest of the wizards back. And Harry does have the power to control dementors.
So, to summarize the above—Harry is the only person who can truly control dementors, and in his mind, Death has no speed limit. If Harry can figure this out within the remaining 60 seconds—Voldie and Death Eaters simply don’t have any chance.