@john26, it's up to you, i think it's still a useful tutorial to help understand how rendertarget works. the disclaimer that setclip makes the tutorial bit obsolete is in the tutorial:
"Remark: since the original publication of this tutorial, real clipping capability was added to Gideros, thus now it's easy to clip using the Sprite:setClip function, see Docs.giderosmobile.com for details. Nevertheless this tutorial remains to be a good introduction on how to use renderTarget. "
so again, it's up to you if you want to include it or not.