but that's the on going trade off between time spent improving your physical conditioning and time spent on skill motor pattern work, I've commented before that for many it seems the balance is tipped to far in favour of skill and no where near enough conditioning and,strengh work.
think of hopping as one legged jumping and it makes more sense, most real world jumps are one legged take a run at it jumps, , even jumping in the,air and kicking is a hop/ one legged jump.
the major advantage of hopping is how it works the calf muscle, a much neglected muscle group that can only really be worked hard by hopping, two footed jumping is very quad dependent to get momentum that takes the load of the calf some what.
there is no need to neglect you lesson over it. Try hopping up the stairs every time you go for a pee, that will have you calf in fine,shape in no time