As I mentioned in the PEP, we already violated this orthogonality by disallowing return, break and continue in except* clauses. I think it’s not a coincidence that both cases are related to exceptions: what’s happening here is that the two program control flows (normal and exceptional) are interacting, and this can become confusing.
AFAIK, at the time that ALGOL '68 was developed, finally wasn’t a thing, nor was bare raise. Once an exception handler was handling an exception, this exception was no longer in play and we were back in normal control flow. Now this is no longer the case - we move back and forth between the program and the exception’s unwinding process, and this complicates matters in a way that ALGOL '68 didn’t need to contend with.
An appendix is a good idea, I’ll do that. Thank you.