Yes, good idea

Oh, yes. That might just work

This would involve me having to do a condition assessment of about 500000 books. I can't!

Also once came across a thesis about an anonymous library where lots of info had been sent "by email from the librarian". Except it was obvious the author was writing about her own library, and I don't really believe she sent herself emails

I've come across "knowing in practice"

This is a genuine request for advice.

How do I deal with this kind of "evidence"

I've also noticed over the years that (plentiful) German theology in Dissenting libraries has German binding, but the odd German book in Anglican collections has English binding. AFAIK I'm the only person to have noticed. But I can only just wave vaguely at any evidence

Crucially my supervisor is a church historian, and has never come across this as a problem before.

He particularly thought that maybe I didn't need to put so much effort into bilbliographically correct citations of 18th century laws referred to in passing.

Might set one up. A bit like dial-a-disc, but I choose what the caller hears.

Had to read this twice, as initially interpreted "quote agency" as a literary enterprise and thought talking to them sounded lovely.

Kit Marlowe.
(He was angry because I was sitting where he wanted to nap)

Expression seems pretty accurate to me

Actually, you would. It's exactly as much as is written on the Wikipedia article on the subject. Plus some bits that were edited out a few years ago.

You would not believe how much I know about how the Berlin subway system operated during the cold war.

Yes, particularly to myself

Certainly a lot of some kind of salt