That would only make sense if coinbase was down for several days at a time. If it was only down for a few hours then that's nearly not enough time for enough money to flow in (aren't wire transfers batched per day rather than processed in real time?). It also doesn't answer my earlier question of "why don't they just stop pumping before they run out of money?".
>A big Canadian exchange, quadrigacx that blew up ~2 years ago was doing all sorts of tricks like this.
Perhaps that's exactly what's happening at coinbase, but pointing to them being down when there's high trading volume isn't a convincing argument.