Signal, event and bicycle

[Michael]

I saw the announcement about new signal some time ago.

D Language is amazing, but in this case it's looks like little 
bit complicated.

I written my code in terms of simplicity: using a standard 
language features and simple design.

In the broadest sense it was a little experiment. As result at 
final stage I have next questions:

- why with this simple task we should use a rt_... magic?
- why rt_... hooks is used like dtors?
- why to write a simple iterator over container and calling its 
data we need above magic?
- if I will see problems in signals implementation, why I need to 
know about "hidden" references that GC not sees?
- what if rt_... or GC behaviour will changed and it's will not 
possible using standard and documented language features in this 
case?