I agree that the best case (uh, best for people who like Kessler cascades?) is that the new fragment has a perigee equal to the location of the collision, and a

I agree that the best case (uh, best for people who like Kessler cascades?) is that the new fragment has a perigee equal to the location of the collision, and a higher apogee. That means, yes, that it will suffer whatever degree of drag was present at the altitude of the collision. However. The grandparent post claimed that "Fragments that are ejected from the collision cannot have more than energy than they had originally, nor can they change direction very much", which I think is clearly what I addressed in my comment, and I stand by my correction of that, and your reply doesn't address this at all. Also, with respect to "you _cannot_ launch them into a higher orbit", you just agreed that you can have a higher apogee than the collision. If the input satellites had perigees lower than the altitude of collision, you can also have a lower perigee. More velocity at this point on the orbit, higher apogee, higher perigee.... So how do you figure you cannot have a higher orbit?