Yes, I did mean 6 hands on one piano!
Digby - yes it was us at Cheltenham (15 and under class). I had worked really hard with the girls on playing well together as an ensemble - ie getting a good balance between the parts, and staying in time with each other. I too thought they should have made 2nd place, on that basis (thanks

) - the 2nd place girls were poorly balanced (primo mostly drowned out by other 2) and timing was poor (but they played a more ambitious piece..). However, the initial aim of doing the trio was to get the girl in the middle to perform in public for the first time - job done! The young lady you mention is from Maryland USA.
I thought several of the adjudicators were ready to be put out to pasture. The chap who adjudicated the choir classes for our school was hopelessly old fashioned - criticised us roundly and had nothing, but nothing nice to say to the young folk, grrrr.