Maybe it's supposed to be used when playing live?

Live? Good one. Possibly usefull. Then the marketing machine could say that.. I got the impression it was some 'anti clipping' feature.

Seems like a "security Blanket" type thing...

Just for those who might not be so clued up, and drive things too hard, as a safety feature they include this option???

I dont know......

Well, it's pretty easy to get the Virus to clip internally at times with patch volume turned to 127, and I doubt everyone knows about the LED mode where it tells you if it's clipping. Seems like a useful enough feature to me...

just read this on the RME site...
"A soft-limiter, which has been tuned especially for musical instruments, efficiently prevents overloads of the A/D-converter."

At least their version is suggesting an analog stage before the converter!

How do you figure that grs?

You can have digital clipping too