On Young Wizards not-crossovers:

Mmm. I am reminded of the pair of (brilliant) Yuletide stories by oniongirl in which the issue of fictionality arises as we have characters traveling to and from Gotham City in one 'verse to NYC in the other:

"Do you think they're going to remember?" Kit asked, "You know,
that they were here...I mean, that they were here and found out
that they aren't...aren't..." He trailed off, because it was
difficult to think of Tim or Dinah or any of them as...fictional.

"Tell you what, why don't you test it? Travel to a universe where
we're fictional, and then come back and see what you remember."

On Duane's Wounded Sky:

I would swear on a stack of wizards' manuals that when I first read that book lo these many moons ago, I caught the phrase "further up and further in" somewhere in the climactic sequence, which would arguably make that novel canonically Narnian. That said, I have on more recent attempts at rereading been wholly unable to find that phrase again.

On Mary Poppins:

I ended up using the title for something else, but I had an idea at one point for a story in which Mary was a rogue Watcher in the Buffyverse. (OTOH, I actually wrote the story in which we establish that Mary was governess to Sherlock and Mycroft Holmes back in the day.)