Cryptic crossword No 1,931

Theme Clue: x = 6d

Hopefully this puzzle is a slight improvement from the last one, I've got a couple of queries which I will put in a reply to this comment to avoid spoilers. I found theming the crossword to be very enjoyable, and was surprised how many themed words I managed to get in after a few tries (14). I think it helped to have a large number of possible themed words, as there were more that words I could abandon if they just wouldn't fit.

Welcome back Layton. Particularly ambitious, incorporating a theme in your second puzzle! Unfortunately, it was lost on me as I’m not familiar with the field from which you draw. Nonetheless, I appreciated 8a, 11a, 13a, 26a, 4d, 6d, 16d, 18d among others. Notwithstanding any technical glitches, your surfaces are generally impressive and often have an inventive, witty streak that adds to the fun for solvers. A bit more detailed discussion in reply, spoilers…

Thanks Layton for a solid crossword. My favourites were 9a, 25a, 1d, 16d, 17d,and 19d. Unfortunately the theme was lost on me but it's impressive nonetheless. More in reply.