Are a lot easier when you do a piece that is nothing but rolled chords. It’s still a little dicey in places, but it’s not bad. Keeping my hands relaxed (and my shoulders as well) is a big part of it. I still have to go super-slow to make sure they stay pinned down, though.
A while back, I remarked that it would be nice to be able to roll chords on the harp without sounding like I had thrown a handful of beans at it. I think I’ve got that down better, and unsurprisingly, the biggest help is to simply hear each note in my head individually. Not knowing what to aim for means you’re highly likely to not hit it.