Using change comment; using auto-combine

[lethe]

Can something be said in the manual about using the change comment? I see librarians f.e. replacing covers or changing page counts without clarifying why and/or stating a source.

(I know when I started out as a librarian I didn't have a clue what 'change comment' meant. I completely misinterpreted it, thinking 'change' was the verb and 'comment' the direct object. I had no idea what comment I should change, so I never filled it in. :) )

Same with 'auto-combine' on the combine page. I don't think that is explained anywhere. A fellow librarian tried to enlighten me once, but I didn't really get it.

(I clicked the auto-combine link just now on a combine page that only had two books and I saw this pop-up message: "This will automatically combine any titles that have the same name (excluding any part in parenthesis). Are you sure?", so that does explain it somewhat, but it would be nice to know beforehand what exactly we are clicking on.)