It can work very well at DHS, it's just change that it seems everyone hates at all times.
DHS has a huge advantage over DLR in that it has a dedicated theater for F!, instead of shutting down the walkways around Rivers of America to make seating for the show. The fastpass for Fantasmic! and World of Color at DLR are separate from the rest of your fastpass system, in that getting one early in the morning doesn't prevent you from getting another fastpass immediately for a different attraction. As for park hopping, it's the same issue that you've always had a WDW park, you have to be in the park to get the fastpass. The people that plan to go to DHS and stay all day are going to end up with the better seats than those that just want to show up before the show in the evening. Unfortunate for WDW is that park hopping is so time consuming because of the size, but it does really do wonders for the immersion factor, unlike DLR where park hopping is really encouraged because there is only 110 yards between entrances of DL and CA, but you have more intrusion of the "outside" into the parks because there is a major freeway and surface streets right outside both parks.
BTW, I'm having an interesting time with this, and there is nothing personal intended or taken in this. It's helping me get some of my thoughts together in a more organized manner about the comparison between WDW and DLR. Wish I lived a little closer to either park so that I could go more often, but that allows me to continue dreaming about a Disney Texas parks system.