Ha haa, nice one,
Zil! And good to see somebody else to scrub off the rust and join
I thought it might be that, to be honest, but I didn't even look it up, because I dismissed it with "that one is about books, there certainly isn't anything about letters!" Wrong, of course.
Ah Sam! I really like that detail, though, now that it's been brought to my attention. It is sort of completely random, unnecessary elaboration - but I like it!