[traditionalist]

What sense does it make to forbid an ex-priest from lectoring at Mass? Or teaching in an RCIA program?

It makes perfect sense. It prevents someone who wants to have it both ways from finding a "back door" into the ministry.

The law is the law. No bishop is above papal legislation, collegiality nonsense not withstanding.

[sinkspur]

It prevents someone who wants to have it both ways from finding a "back door" into the ministry.

To show you how silly the canon is, an ordained priest is also an ordained lector.

IOW, he is actually charged, by the Church, to read at Mass.

It makes no sense to allow him not to.

If you think that reading a New Testament reading is a back door into the ministry, then why not say that of every layman who lectors?