A rolling loose is purely for distance, not accuracy. The rolling loose imparts maximum velocity and oomph to an arrow when done properly, while allowing the full draw to come fairly easily. For target shooting you'd never use it.
The biggest hurdle for target shooting a warbow is arrow spine, I find. By the time you're shooting 120#, the arrows need to be half an inch thick, and you just can't sensibly spine those. Well, that's not true, you can, but most don't! It's also very hard to be able to hang on to consistency when using big bows, so for target shooting after a few arrows you're running out of steam.
As far as I'm aware, most warbow shooters use much lighter bows (70 - 90lb) for any comp shooting, and go up to full weight for distance, clout etc. That's what I do, anyway!