Argh! Good, I think. It's not based on any massively obscure knowledge, and I think all the groups work well, but I didn't sort a single one in the time. I spotted two, and identified three once time ran out.

O line seems a bit of a stretch

@Fam. That's the line I almost solved in the time. There was a group in one grid I did a few days ago that was countries missing their first and last letters. I didn't solve that one, but I had it in my mind when I was trying this grid, and I saw the O group, just before the time ran out.

@Dagoba. That’s the beauty of these grids I guess. There'll be some connections that one person thinks ridiculously obscure and another person thinks obvious. The more grids I do the more techniques I become aware of so that’s another trick I’ll have to look out for ( though I still don’t think I would have got it ). The only line I got was the Castle one and that was only because I thought the words ‘looked’ like they went together, a cunning technique of mine :)

Nice. Ideas were good,nice and easy except the O group. I only saw that connection once the grid was resolved.