Interesting to see the different responses from drxx and candledave. For me, my traditional position, which still holds for most other puzzles, is that of drxx - having to use aids spoils the enjoyment. For the Listener I’m coming round to candledave’s position, and the more I accept I will have to use aids the more I’m enjoying it. For this puzzle I’ve used aids pretty much from the outset, but I don’t feel it has detracted much, if at all.