The attached DOE report, Number DOE/PC79816-4, was published in the late Eighties and reveals that, even then, detailed research was being conducted on improved Fischer-Tropsch catalysts for the conversion of coal into liquid fuels.
It relates work done by/for the DOE's own Pittsburgh Energy Technology Laboratory. And, it is quite specific; focused on seeming minutiae of comparative catalyst performance in the process.
In other words, they weren't trying to make the process work, they were making it work better. And, since SASOL, who is mentioned in the body, seem to have had it pretty well in hand for many decades now, and we've made it even better, it makes one wonder, does it not, why the heck we're not just doing it.