Are you thoroughly rinsing the starch out of the rice in the 1st cook? This may sound silly, but many people don't know how to cook rice. You need to rinse many times (until the water stops becoming a cloudy-white color).
Also, you need to "par-cook" the rice the 1st time, so it won't get super mushy the second time. It will continue to cook a bit as long as it stays warm, so factor that in as well. Consider using less water than normal for a partial cook because the grain won't soak it up. The ratio for normal rice is 1 part rice, 2 part water, so maybe consider a 1:1.5 ratio. The grain should still be just a little bit crunchy when you proceed to dry it out.
I haven't tried this yet, but after spending a few years as a chef, it only seems logical. I have, however, par-cooked rice (risotto, etc) before, and it is a very similar concept.