I think Oppo means you send one HDMI direct to the display, and the other to the SSP. I think it is mainly so that AVR's and processors that are not HDMI 1.4 compliant can avoid clogging on 3D video. The SSP passes 3D video so no need for the dual outputs.
The SSP has 2 outputs, so you can feed the 2 displays that way.
I thought what they said in the manual was that to get the highest quality of audio via HDMI, up to 192k, one needs to split video into HDMI1 and Audio into HDMI2.
If I send video only to HDMI input of SSP, I can't hook up the audio from HDMI2 to that input.
If I send video only to the projector, I can't use SSP to switch between projector and TV.
That's the issue.