>  - I still think we should turn on --slow mode for our buildbots soon,
> but this will cause noise. I'd really like some inputs on this - maybe
> someone would like to help clean up the 'slow' vaildate failures?
> Bonus points for this, since you don't even have to

That's a great goal, but --slow enables compiler debug assertions,
which seem to trigger real errors (full log of failures attached).