Close left eye, and look at LH, close Right eye,and look at RH.
Then close both eyes. After that open them but don't play.But seriously, why air your dirty laundry here? Is it that tough a stain that it's been a couple of months already?
I contracted the fingers to play the octaves like a quick grabbing motion. This motion significantly reduced the downward smashing. It also bounced the hand back to position and eliminated extraneous tension. This change in technique directly translated to less strain and increased accuracy and ease. I hope these are desirable attributes.