DIP1001: Exception Handling Extensions

[Superstar64 via Digitalmars-d-announce]

On Sunday, 10 July 2016 at 20:30:56 UTC, Stefan Koch wrote:
> On Sunday, 10 July 2016 at 19:55:37 UTC, Superstar64 wrote:
>> link: https://github.com/dlang/DIPs/pull/9
>> file: 
>> https://github.com/Superstar64/DIPs/blob/exception_extensions/DIPs/DIP1001.md
>
> You don't have to use gc-allocated exceptions anyway.
> Allowing to throw any type makes chaining impossible.

Can you please explain why it makes chaining impossible?