Actually this thread is still relivant to those who will google looking for answers and why on board and sound blasters are not used by anyone expecting to make good recordings.  

Interesting test, hopefully it would match Sonars calculations. 
That's sort of like the offset test but adds testing the input echo to the formula. 
The reason for the offset test is to see if the Audio drivers are telling the truth to Sonar.. seems some do not. There's a 3 page thread somewhere in the hardware form where a bunch of us tested different interfaces. As expected all the interfaces we trust passed with flying colours.. it's the doggy interfaces ( drivers)  that don't.. 
Most have said that the RTL test application always matches  what Sonar reports but you gotta admit it's a cool app. 
 
I didn't run that test yet on my new system for the 6i6 or Tascam  so will see if I get a chance and I'll post a shot.. I might start a new thread to keep confusion away as this is drifting off topic a bit. 
 
Rewguarding the SB screen shot, My buffer settings are what ever the default must be. This test was done on my old DAW which is now my office computer. I have since swapped it out for this other old PCI card made by Card Delux.. it is old but still supported by the company and it has solid ASIO drivers. It's test came out bang on. I see in the picture I didn't run it under WDM mode even though the title say's so.