I had a similar experience to most with this. Challenging but a relatively quick finish. Same new word for me (I said it over and over to myself in an attempt to learn it and increase my vocabulary but on writing this I realise I’ve already forgotten it - doesn’t exactly fall off the tongue!).
I also was surprised by 8 across but realised after checking the answer in Chambers that one of its definitions means ‘to spread over (a place)’. I’m more like to remember that but doubt I will use it beyond crosswords!
My FOI 17,25 and LOI inexplicably the relatively easy 20. My COD was 6 for the clever word play despite needing Google to confirm the answer… still won’t remember it though!