Could be simplistic statement on my part but is is actually simplistic to focus entirely on the speed tape. There is zero evidence they even glanced in the direction of the speed tape or had capacity to process whatever data was there in whatever format. Since they were incapable of processing high angle of attack visual cues outside the window or 80 lbs force on the yoke it is even more unlikely they had capacity to process any instrument readout, analog or digital. But if you 'understand' Asiana 214 better than anybody else perhaps you can explain what happened then...