SBR and SBL placement question

OK, so I've currently got a 5.1 system set up as described in the diagram. I'd like to add 2 more speakers, but I don't have the space behind the couch, it simply isn't an option. I like the immersion that the SR and SL speakers give me when they're placed right next to the couch. From my understanding, the SBR and SBL speakers are hardly used, so I don't want to move my SR and SL to the side and put the SBR and SBL where they used to be.

I know this is probably a terrible idea, but I was thinking of putting the SBL and SBRs on the side of the room (indicated by the dotted lined rectangles in the diagram). and let the Audyessy setup autocalibrate them. Is this a terrible idea? Should I just stick with 5.1?

thanks in advance!

Hmmm, sound advice (no pun intented ). I'm thinking perhaps I'll try putting the SL and SR where they should be (to the side, where the dotted lines are in the diagram). and put the SBL and SBR where next to the couch, slightly behind. If I'm not really satisfied with that sound, then I'll just revert to a 5.1 setup.

thanks Sanjay

OK, how's this revised:

The problem is that the space labeled "Unusable Space" is actually a high traffic hallway. Behind that begins the kitchen with no wall close enough to mount speakers. I could move the speakers all the way up so that they're against the wall, but at a 90 degree angle to listener's ears on the couch. What I'll do is cut enough wire to move them to that position then try different ones. Worst comes to worst, I jump down to a 5.1 setup I guess, but I want to try what I can before I relent.