This week's offering is a themed, or partially at least, crossword by Paul.
I'm useless at gauging difficulty, so all I'll say is that it really does help and make a difference once you figure out the themed answers.
There's the usual array of clue devices but I think there might be a couple more first or last letters than usual.
My COD is 17a for it's smooth surface and clever definition.
Thanks to Paul.