Tell me about your experience doing ATP-ASEL

I just crossed 1500 hours, and am interested in doing ATL-ASEL. I know that's a fairly unusual pursuit, as almost everyone does it multi-engine. I've read through the ACS, but I have yet to find anyone who holds the certificate, or any instructors who have trained someone for it.

Would be interested in hearing about your experiences -- how you trained for it (or how you've instructed someone pursuing it), how focus areas for the oral may have differed from the ATP-AMEL version, and any interesting nuggets, gotchas, or takeaways.

(And yes, I know it has very little practical application!)