[jd]

It's even worse. For top level functions it can throw the UNION of the exceptions thrown by the functions it calls. Therefore, by changing a low level function's exception signature the exception signature of all higher level functions changes too. That always worried me, but it's doesn't seem to be a big deal in practice.

[nostrademons]

It's a huge deal with checked exceptions in Java. You have to change the signature of every caller, and so on, when you change a low-level function. Abstraction leakage galore; it's why many libraries just throw a single generic exception type whenever anything goes wrong (which defeats the purpose of exceptions) or subclass RuntimeException (which defeats the purpose of checked exceptions).

Unchecked exceptions don't seem to be a problem, because oftentimes you don't care what specifically went wrong, you just need to know that something went wrong and abort appropriately.