Thanks for all the suggestions.
As luck would have it we settled on fruit cake, (mildly) smoked salmon, french bread and some mild cheeses with plenty of water to cleanse the palate. Tasting paused for the food and resumed afterwards. We spent three or four hours trying about fifteen different whiskys (note: just small puddles of each!) using tasting notes sheets and also doing some blind tasting. After which I decided tasting wasn't keeping to strict scientific method and my head was starting to throb.
Very pleased that, in blind tasting four different Glenfiddichs, I ranked them in the order in which one would expect them to be marked: 12yr, 15yr, "Special old reserve" and 18yr old.
Most popular were Aberlour, Dalwhinnie 15yr and Lagavulin special reserve; least popular was Jim Beam by a country mile

Well, one needs to set the boundaries!