Without seeing the code in question, we really can't answer this. Have you, for the supposed sake of readability, decided not to code certain abstract cases as abstract cases, instead enumerating over them instance by instance? This is one case where fewer lines may actually make the code easier to maintain.

Is the program 300 straight lines of code, or have you taken the opportunity to group related functions into subroutines so that the main body of the program is short and sweet, relying on the functions to fill in the details?

Do you use idiomatic and straight-forward Perl, or is it longer because you are trying to clarify kludgy methods?

Of course, I'm only playing devil's advocate here. The odds are someone who thinks line count is a significant measure of anything (especially with respect to Perl) has no clue what else to say. It is also possible that said boss is under the impression that one liners and JAPHs are the be-all-end-all of Perl mastery and that code that doesn't look like that is somehow less worthy. If it doesn't look like a cool hack it must not be. Personally, I think that's a dangerous mentality.