That was my first thought too. I remember the attention it got. And of course it was not so ephemeral, as people ensured the poem was captured, since in that case people knew it advance it would self-destruct.
It's an interesting poem, and one that probably was read far more because it was published the way it did than if it had been published the normal way. While I enjoyed poetry, it is the first and only time I've rushed to read a newly published lyrical work.
It's beautifully constructed in that it is about the distinction between memory and reproduction, and where the poem represents a reproduction of Gibsons own memories, the self-destruction served to make the book itself an event and creation of memories about the reproduction of the poem even in many cases in people who never got around to reading it, but just read about it.
It's also interesting because one of Gibsons own comments about it is about how we tend to remember the past in light of the present, not the way it actually was, and thinking about how I remember the work, I realise I have memories of text fading, but 1) my memories don't match how it was presented, 2) I never saw the original anyway.
I have distinct images of reading it in light blue on darker blue, but I would have read it on my Amiga. Those are not the Workbench colours, and the offline readers I used did not use that colour scheme - it's more likely that I'm confusing it with reading texts shared on floppy on my C64, years before. So our memories of Agrippa are themselves now an example of the theme of the poem itself.
Ironically, it is a cooperative project with Dennis Ashbaugh who designed the book as an art piece, and came up with the concept of the self-destruction, but whose part of the work has remained the lesser known part of the "package" despite (or because) not being the part to self-destruct.