Tierazon is an odd one, yes .. nmsmith is possibly the most experienced in its use .. he often blends them into the background of his pieces
it is mostly a zoom and apply a filter type of experimentation process from what I can tell from my time with it
try apophysis for a while .. you can start by just exploring the 'random' fractals it generates .. do small (640x480) test renders so that you have a better idea what it actually looks like .. change the gradients .. then move up to the editor later .. move some triangles around
it's just a matter of finding your groove .. apophysis is capable of many looks and styles