This would require some other preparations like handraising or otherwise habituating the animals to people so they wouldn't be totally stressed out by being moved in and out of the enclosures. Handraising them would also allow them to be fed the target grass species from a young age to hopefully influence their food choices later. The reason I think this is a realistic experiment is because it could be framed as a pro-conservation move by the landowner, and it could also potentially be a grant-funded postdoc type of project. It would not be something that I would think is a good idea for wider use but since this property contains up to .4% of all remaining coastal sage scrub habitat, a positive impact on that area alone would not be inconsiderable.

The first stop is at a Mediterranean grassland. Nearly all of the native Southern California grassland which was dominated by perennials has been replaced with invasive annual grasses. The elevation is around 300 feet above sea level and the climate is Mediterranean or semi-arid warm steppe in the Koppen classification. Temperatures are mild and the weather is mostly sunny year round. An average of 300 mm of precipitation falls each year mostly between December and March. Plants here are drought-adapted since most of the year has very little rain. They also tend to be somewhat adapted to fire of varying frequencies.
This is Mission Trails Regional Park. There are two large sections of grassland in the park, mostly surrounded by sage scrub and chaparral communities. Park literature attributes the non-native grasslands to past overgrazing. Once the native ecosystem is disturbed and annual grasses gain a foothold they provide fuel for more frequent and faster-moving fires and then quickly grow in the burned areas depriving the newly sprouting shrubs of sunlight and water. The area that makes up Mission Trails Park is known to have been settled by the Spanish in the 1760's so there has been plenty of opportunity for the introduction of European grasses and disruption of native plant communities.
        Visible in the background are hills covered with sage scrub and chaparral; sycamore and oak trees are visible in middle ground where the San Diego River provides a corridor of riparian habitat.
Here is where the non-native grasslands transition to sage scrub and chaparral communities. The altitude increases on these hills to about 650 feet. It appears that the grassland gives way to native shrubs more and more as the altitude increases. I don't know why this would be but some factors that I thought might contribute to this phenomenon are: grass seeds are less likely to be dispersed uphill than downhill; cattle and human disturbance may have been concentrated at the lower altitudes because it they were easier to access and closer to the river. 