"playing with a design whose primary purpose was plutonium production "
True. As all 1st generation Russian and European designs were. Only the PWR or the CANDU was not "Born to breed" to coin a phrase. The US already had plenty of Pu from other designs and the Canadians didn't want bombs (althouth apparently CANDU is quite a good little Pu factory. Could Canada be the world's most covert nuclear super power?)
All other designs were.