Yes separate. With Dirac you cannot see the combined/average trace. (That would be a nice feature for Dirac to add for sure). I’d need to measure with REW to see that and I haven’t got to that yet!Since the first graph shows two lines, I assume they're the separate outputs, not combined.
What does the combined output look like?
It may or may not be the simple addition of the two plots - the presence of more than one sub alters the way modes are excited in the room, usually for the better.
Edit - Actually I may be able to get that post Bass Control. I’ll go back to that project and see what I can do.