I wonder what is so strange about rule 24. The perlstyle manual page says: space around most operators. Which is what rule 24 is saying, but it's listing the exceptions. The reason I put space between ++ and -- and its operands is that those operators are "large" (two characters).
As for ->, it's a binary operator. I put whitespace around other binary operators, so why not ->? If you don't, you can get long blobs of text, without a resting place for the eyes. Perl should look like English, not German. ;-).