There is a product made by Safer, that is basically just diluted liquid sulfur, You can spray that on the new growth to help prevent the fungus from spreading to it, but the leaves that are already affected are doomed, so it is great that you are removing them.
I don't really always take the time to remove the blackspot, just if I happen to see some affected leaves while I'm picking flowers. Kinda haphazard, like my life
. Pretty much I just make sure that my soil is happy, that makes the plants strong enough to survive blackspot, ect... I guess the concern is that a rose bush could be defoliated, and not build up enough energy to get through the winter. But with happy soil, the plants seem to rebound eventually in my garden, just like a very healthy person can fight off a cold without meds and such. And if any of the roses are going to be weak and fussy, they get culled.
Hope that helps, didn't mean to get all preachy soundin' with plant philosophy. Sounds like you are doing a great job!
I am so flattered that you named me as a "rose" person in this post! Cool.