"If you're not carefully considering every code change, then do you just blindly charge ahead, slingling code, and hoping you aren't on call when it breaks?"
Straw-man. There are degrees. A simple code change in Java may be impossible to architecturally designed rigidity, while a simple change in Perl may devistate an entire architecture. Such changes are not immediately apparent. What is important is to both have power, convience, and the ability to enforce light discipline and future maintainability all in one.
Perl is not a language that makes this automatic. You are much more likely to see Perl code devolve, as it takes incredible discipline to wield. Yes, I know people want to always have that discipline, I do too, but there are times when even we make mistakes.