Just thought I'd post some pics of the wall in question. The bench height is about where the smooth part of the wall finishes. The splashback starts where the rough part of the wall begins.
http://users.tpg.com.au/vgolf/pic1.jpg
http://users.tpg.com.au/vgolf/pic2.jpg
http://users.tpg.com.au/vgolf/pic3.jpg
http://users.tpg.com.au/vgolf/pic4.jpg