std.experimental.testing formal review

[Per Nordlöw via Digitalmars-d]

On Wednesday, 9 September 2015 at 15:20:41 UTC, Robert burner 
Schadek wrote:
> This post marks the start of the two week review process of 
> std.experimental.testing.

Will `runTests` automatically assert that all pure unittests by 
default are parallellized and all non-pure are serialized? If so 
why is the @serial UDA needed?

Will it make use of D's builtin threadpool or will every unittest 
run in its own thread? IMHO, we should strive for threadpool 
usage here.