I have not tried it yet since the more common household 70% isopropyl alcohol is good enough for me with Tamiya Acrylics. To my knowledge, denatured alcohol (which is mostly ethyl alcohol) is more commonly used as a thinner for varnishes. Being water-based, though, it may work with Tamiya Acrylics, but I'm not 100% sure. Best to try on a small amount of acrylic paint first and then spray on a scrap styrene sheet or junk model to see how the finish ends up. Hope this helps.
Cheers,
onyan