I don’t know much at all about E. N. Shaw, the author of an obscure 1983 book about an obscure reactor. I liked the insight from this paragraph, showing an example of why advanced reactor development is so arduous:
Fuel development is a lengthy process, complicated by the fact that the fuel under test is, as already noted, an integral part of the core. From the definition of the particular make-up of samples to be irradiated, a year would pass before they could be inserted into DRE. They had to be fabricated and assembled into elements while the overall core characteristics were being worked out and the safety of the whole system assessed. Irradiation would vary from a single reactor run of about three months, up to several years for those samples taken to maximum burn-up. After that, the elements would be discharged from the reactor and allowed to ‘cool’ for a period to allow radioactivity to decay, following which they could be dismantled and the samples extracted. For highly active elements, this might take six months. Only then could a detailed examination begin and a full analysis would take at least a year. From first conception to the verification of fully burned-up samples, a period of about 6-7 years could thus elapse.
Shaw, E. N. 1983. Europe’s Nuclear Power Experiment: History of the OECD Dragon Project. Pergamon Press, Oxford, loc. 2966.