A lot of monks here (and good programmers in general) favour terse comments directly in the code, along with substantial POD. They likely have the same doubts you do.
I've used a style much like that for a long time, though. I was first exposed to it in a C-shop, and I have seen several advantages with it:
- Maintenance programmers don't have to read code for every sub
- Explicitly states the contract for a function/method
- Leaves room for prose (e.g. ToDo lists, caveats the programmer notes, modification histories for non-CVS environments)
- Clearly separates methods and routines from one another
- Clearly separates general comments from comments about specific lines of code
That said, the better I get at Perl programming, the more my comments tend towards brevity, so I'm pretty sure those wiser monks who dislike this style are on to something.