Problems that are overconstrained often can't be explicitly solved.* Wanting to handle a big range both in front and in back with a Record or Nuovo Record is in this class of problem. Relaxing one constraint allows finding a solution. In the case of my wife's bike, the solution is a 13 - 31 Regina Oro 5-speed FW, with a 40-45 Stronglight 63 set in front. This gives a nice, useful, 35" - 93" gear set, with half-step gearing.**
harvey sachs mcLean va *The proof is left as an exercise for the reader. :-) ** My Hetchins has a 14-28 half-step, with a 44-48 front, which gets me pretty close to the mini-macho criterion, a 100" gear (99.4). But, since it has a granny, the Nuovo Record was not a candidate for this bike.