(Perl's) encouragement of highly individualistic coding styles makes collaborative development more difficult

You know, I've always thought statements like this one rather curious. Just because perl allows the programmer to be expressive doesn't mean that it encourages it. The whole point of the TMTOWTDI motto is to remind programmers that they needn't be constrained by one mode of thought, not that they should strive to do things in as many ways as they can think of.

In any collaborative coding effort there are guidelines (either implicit or explicit and sometimes even evolved) for contribution. These guidelines are social conventions, not technological. Perl's ability to let the programmer code in a multiparadigmatic manner isn't going to affect collaborative development at all except to make it easier. Where else could a few programmers each with expertise in a different programming language all collaborate in a meaningful/useful way but on a perl project?