I mow my pasture (I'm just outside Auburn), but disking has some benefits for fire protection. I keep the area near the house green but I stopped irrigating most of the pasture because then I have to cut it

. If I had a disk, I'd use it around the edges of my pasture for sure.
As far as saftey goes, if you can disk it you can probably mow it. If you're relying on the disks to hold you on a slope you probably shouldn't be on it anyway. But that is just common sense, and as one of my neighbors and I were talking about the other day that doesn't always win

.
If you run a couple of passes with a disk you'll get a better firebreak than you will with mowing. Most of the folks around here hit the edges of their property about now - the seasonal grasses are pretty much done growing, even if we do get a bit more rain. Some wait until the end of May, early June to be sure the growing is done (or hit it again).
I used a tiller one year to try and create the same thing. It worked OK. I would like to pick up a disk one of these days, but I have to have a mower. If you have both, I'd suggest doing both...mow first and then disk it in.
For those of you outside this area (that are interested), the way the weather works here is that we get rain during the winter and then it stops (completely, totally and absolutely) over the summer. The start and stop dates vary somewhat, but you can pretty much count on no rain from about May through September.