I think that option is long gone. But you’re absolutely right, Favour Speed is what does it, and it’s pretty incredible really. I took a typical modern loud cd rip, turned on Favour Speed, and you could actually see all the different sections of a song for easy navigation for editing, whereas before it was nearly impossible to see anything like that. Even if it’s not accurate it’s incredibly cool. And even though people would be told to mix and master to look like that in the first place on an accurate waveform, that’s often not the case at all. Maybe you should Feature Request an option in the Wavelab 9 subforum.
One thing I couldn’t do in Wavelab 5 with either setting is drill down to view 24 bit dither at -120 db at all. 16 bit dither at -80 db I could just barely see the thinnest line when fully blown up. In newer Wavelab you can blow up the waveform to easily see either of those. I often need to do that.