What is the case against a struct post-blit default constructor?

[David Nadlinger]

On Friday, 12 October 2012 at 09:42:19 UTC, Jonathan M Davis 
wrote:
> That sounds like a decent solution to me, but I think that 
> there's a good
> chance that Walter would reject it on principle (since in 
> general, skipping
> the invariant pretty much defeats the purpose of having one).

But he already suggested implementing a _custom_ mechanism for 
skipping the invariant somewhere else in this thread (i.e. a 
"valid" flag) which is arguably even worse…

David