No, but I did play with it a little, and Phillip Lord visited our office once in 2016 to chat about RDF & Clojure. Nice guy! I never really gelled with Tawny Owl because the approach was to be more of a language / REPL-environment for ontology development, rather than a clojure library for ontology development. IIRC it’s not very functional, and macro heavy, but Phil’s goals weren’t so much about bringing this stuff to clojure developers, and seemed to be more about bringing an interactive REPL environment to ontology designers.

Yeah that makes sense. I've been playing with it for a little bit, and I think I'm concluding that it's not a good fit for me either.