Oh, I don’t think either book is trying to hide its provenance, and I remember making fun of them with my friends when they came out*. But my opinion is that they’re incoherent to the point of unreadability, not meant for publication and honestly a rather saddening and involuntary addition to Tolkien’s bibliography. I rather hope that the Pratchett family don’t do the same, for instance. If they already have, I’m sorry to hear it.
*Just noticed that they came out in 1977 and 1980, rather earlier than I thought - the republished paperback editions?